obtained gcc-4.6.4.tar.bz2 from upstream website;upstream

verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
should provide you with a source tree that is binary identical
to the one extracted from the above tarball.

if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
directory might differ from line-endings of the respective
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213 files changed, 16622 insertions, 0 deletions

diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/12790-1.cc
new file mode 100644
index 000000000..99d5eda88
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/12790-1.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out | ios_base::trunc);
+  fb.sputc(pod_uchar::from<char>('b'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>(0));
+
+  // Check that close() writes unshift sequence
+  fb.close();
+
+  fb.open(name, ios_base::in | ios_base::out | ios_base::ate);
+
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>(0));
+
+  fb.close();
+
+  fb.open(name, ios_base::in);
+
+  fb.sbumpc();
+  fb.sbumpc();
+  fb.sbumpc();
+
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/1.cc
new file mode 100644
index 000000000..0a12e7224
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/1.cc
@@ -0,0 +1,87 @@
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_members-1.tst";
+const char name_02[] = "filebuf_members-1.txt";
+
+// Test member functions.
+void test_01() 
+{
+  bool test __attribute__((unused)) = true;
+  const char* name_03 = "filebuf_members-3"; // empty file, need to create
+
+  std::filebuf fb_01; // in 
+  std::filebuf fb_02; // out
+  std::filebuf fb_03; // in | out
+
+  // bool is_open()
+  VERIFY( !fb_01.is_open() );
+  VERIFY( !fb_02.is_open() );
+  VERIFY( !fb_03.is_open() );
+
+  // filebuf_type* open(const char* __s, ios_base::openmode __mode)
+  fb_01.open(name_01, std::ios_base::in | std::ios_base::ate);
+  VERIFY( fb_01.is_open() );
+
+  // Try to open two different files without closing the first:
+  // Should keep the old file attached, and disregard attempt to overthrow.
+  fb_02.open(name_02, std::ios_base::in | std::ios_base::out 
+	     | std::ios_base::trunc);
+  VERIFY( fb_02.is_open() );
+
+  fb_03.open(name_03, std::ios_base::out | std::ios_base::trunc);
+  VERIFY( fb_03.is_open() );
+
+  // filebuf_type* close()
+  std::filebuf* f;
+  f = fb_01.close();
+  VERIFY( f );
+  VERIFY( !fb_01.is_open() );
+
+  f = fb_02.close();
+  VERIFY( f );
+  VERIFY( !fb_02.is_open() );
+
+  f = fb_03.close();
+  VERIFY( f );
+  VERIFY( !fb_03.is_open() );
+
+  f = fb_03.close();
+  VERIFY( !f );
+  VERIFY( !fb_03.is_open() );
+}
+
+int
+main()
+{
+  test_01();
+  return 0;
+}
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-1.cc
new file mode 100644
index 000000000..508261ba2
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-1.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.close();
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-2.cc
new file mode 100644
index 000000000..0a4bdb3c1
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-2.cc
@@ -0,0 +1,82 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+// 27.8.1.3 filebuf member functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+  fb.in_avail(); // showmanyc() should have no effect on close().
+
+  VERIFY( !cvt->unshift_called );
+  fb.close();
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-3.cc
new file mode 100644
index 000000000..fe0624d10
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-3.cc
@@ -0,0 +1,81 @@
+// Copyright (C) 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+// 27.8.1.3 filebuf member functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return codecvt_base::error;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should fail if codecvt::unshift() fails
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+
+  VERIFY( !cvt->unshift_called );
+  filebuf* ret = fb.close();
+  VERIFY( cvt->unshift_called );
+  VERIFY( !ret );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-4.cc
new file mode 100644
index 000000000..e54c61682
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/12790-4.cc
@@ -0,0 +1,81 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+// 27.8.1.3 filebuf member functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+  fb.pubsync(); // Does not call unshift()
+
+  VERIFY( !cvt->unshift_called );
+  fb.close();
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/2.cc
new file mode 100644
index 000000000..c1a0f79c8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/2.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+#include <fstream>
+#include <ext/stdio_filebuf.h>
+#include <testsuite_hooks.h>
+
+// Verify that std::filebuf doesn't close files that it didn't open
+// when using the following std::filebuf ctor:
+//
+//      std::filebuf(__c_file_type*  __f,
+//                   ios_base::openmode __mode,
+//                   int_type  __s);
+//
+// Thanks to "George T. Talbot" <george@moberg.com> for uncovering
+// this bug/situation. 
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_02[] = "filebuf_virtuals-2.txt"; // empty file, need to create
+
+void test_02()
+{
+  bool test __attribute__((unused)) = true;
+  int close_num = 0;
+
+  // read (ext)
+  FILE* f2 = fopen(name_01, "r");
+  VERIFY( f2 );
+  if (f2)
+  {
+    __gnu_cxx::stdio_filebuf<char> fb(f2, std::ios_base::in, 512);
+    close_num = fclose(f2);
+  }
+  VERIFY( close_num == 0 );
+
+  // read (standard)
+  FILE* f = fopen(name_01, "r");
+  VERIFY( f );
+  if (f)
+  {
+    std::ifstream ifstream1(name_01);
+    VERIFY( ifstream1.is_open() );
+    std::ios_base::iostate st01 = ifstream1.rdstate();
+    VERIFY( st01 == std::ios_base::goodbit );
+    close_num = fclose(f);
+  }
+  VERIFY( close_num == 0 );
+}
+
+int
+main()
+{
+  test_02();
+  return 0;
+}
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/3.cc
new file mode 100644
index 000000000..a5db2aed6
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/3.cc
@@ -0,0 +1,89 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+// NB: This test assumes that _M_buf_size == 40, and not the usual
+// buffer_size length of BUFSIZ (8192), so that overflow/underflow can be
+// simulated a bit more readily.
+// NRB (Nota Really Bene): setting it to 40 breaks the test, as intended.
+const int buffer_size = 8192;
+//const int buffer_size = 40;
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_02[] = "filebuf_virtuals-2.txt"; // empty file, need to create
+const char name_03[] = "filebuf_virtuals-3.txt"; // empty file, need to create
+
+class derived_filebuf: public std::filebuf
+{
+ public:
+  void
+  set_size(int_type __size) { _M_buf_size = __size; }
+};
+
+derived_filebuf fb_01; // in 
+derived_filebuf fb_02; // out
+derived_filebuf fb_03; // in | out
+
+// Initialize filebufs to be the same size regardless of platform.
+void test03()
+{
+  fb_01.set_size(buffer_size);
+  fb_02.set_size(buffer_size);
+  fb_03.set_size(buffer_size);
+}
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  typedef std::filebuf::int_type 	int_type;
+  typedef std::filebuf::traits_type 	traits_type;
+  typedef std::filebuf::pos_type 	pos_type;
+  typedef std::filebuf::off_type 	off_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  std::filebuf 				f_tmp;
+
+  fb_01.open(name_01, std::ios_base::in);
+  fb_02.open(name_02, std::ios_base::out | std::ios_base::trunc);
+  fb_03.open(name_03, std::ios_base::out | std::ios_base::in | std::ios_base::trunc);
+
+  // NB Have to close these suckers. . .
+  // filebuf_type* close()
+  fb_01.close();
+  fb_02.close();
+  fb_03.close();
+  VERIFY( !fb_01.is_open() );
+  VERIFY( !fb_02.is_open() );
+  VERIFY( !fb_03.is_open() );
+}
+
+int main() 
+{
+  test03();
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/4.cc
new file mode 100644
index 000000000..cd4f5e15b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/4.cc
@@ -0,0 +1,73 @@
+// 2003-05-19  Paolo Carlini  <pcarlini@unitus.it>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// Test that upon filebuf::close() 27.8.1.1,3 is enforced.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_02[] = "filebuf_virtuals-2.txt"; // empty file, need to create
+
+void test_04()
+{
+  typedef std::filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  std::filebuf fb_01, fb_02;
+  char buffer[] = "xxxxxxxxxx";
+
+  // 'in'
+  fb_01.open(name_01, std::ios_base::in);
+  VERIFY( fb_01.sgetc() != traits_type::eof() );
+  VERIFY( fb_01.sbumpc() != traits_type::eof() );
+  VERIFY( fb_01.snextc() != traits_type::eof() );
+  VERIFY( fb_01.sgetn(buffer, sizeof(buffer)) == sizeof(buffer) );
+
+  fb_01.close();
+
+  VERIFY( fb_01.sgetc() == traits_type::eof() );
+  VERIFY( fb_01.sbumpc() == traits_type::eof() );
+  VERIFY( fb_01.snextc() == traits_type::eof() );
+  VERIFY( fb_01.sgetn(buffer, sizeof(buffer)) == 0 );
+
+  // 'out'
+  fb_02.open(name_02, std::ios_base::out);
+  VERIFY( fb_02.sputc('T') != traits_type::eof() );
+  VERIFY( fb_02.sputn(buffer, sizeof(buffer)) == sizeof(buffer) );
+
+  fb_02.close();
+  
+  VERIFY( fb_02.sputc('T') == traits_type::eof() );
+  VERIFY( fb_02.sputn(buffer, sizeof(buffer)) == 0 );
+}
+
+int
+main()
+{
+  test_04();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/4879.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/4879.cc
new file mode 100644
index 000000000..9d2c647ca
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/4879.cc
@@ -0,0 +1,108 @@
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+ 
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+#include <fstream>
+#include <iostream>
+#include <cstdlib>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+// No asserts, avoid leaking the semaphores if a VERIFY fails.
+#undef _GLIBCXX_ASSERT
+
+#include <testsuite_hooks.h>
+
+// libstdc++/2913, libstdc++/4879
+// John Fardo  <jfardo@laurelnetworks.com>, Brad Garcia <garsh@attbi.com>
+bool
+test_04()
+{
+  using namespace __gnu_test;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_fifo1";
+  semaphore s1, s2;
+
+  signal(SIGPIPE, SIG_IGN);
+  
+  unlink(name);
+  if (0 != mkfifo(name, S_IRWXU))
+    {
+      std::cerr << "failed to create fifo" << std::endl;
+      exit(-1);
+    }
+  
+  int fval = fork();
+  if (fval == -1)
+    {
+      std::cerr << "failed to fork" << std::endl;
+      unlink(name);
+      return false;
+    }
+  else if (fval == 0)
+    {
+      std::ifstream ifs(name);
+      s1.wait();
+      ifs.close();
+      s2.signal();
+      exit(0);
+    }
+
+  std::ofstream ofs(name);
+  s1.signal();
+  s2.wait();
+  ofs.put('t');
+
+  /*
+   * ISO/IED 14882:1998(E) 27.8.1.10.4
+   *
+   * void close();
+   *
+   * Effects:  Calls rdbuf()->close() and, if that function fails
+   * (returns a null pointer), calls setstate(failbit)...
+   */
+  ofs.close();
+  if (!(ofs.rdstate() & std::ios::failbit))
+    {
+      test = false;
+      VERIFY( test );
+    }
+
+  unlink(name);
+
+  return test;
+}
+
+int
+main()
+{
+  return !test_04();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/5.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/5.cc
new file mode 100644
index 000000000..25ae66b41
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/5.cc
@@ -0,0 +1,106 @@
+// 2003-05-20  Paolo Carlini  <pcarlini@unitus.it>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// Test that upon filebuf::close() 27.8.1.1,3 is enforced.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_02[] = "filebuf_virtuals-2.txt"; // empty file, need to create
+
+bool overflow_called;
+bool underflow_called;
+bool uflow_called;
+
+class Close_filebuf : public std::filebuf
+{
+public:
+  int_type overflow(int_type c)
+  {
+    overflow_called = true;
+    return std::filebuf::overflow(c);
+  }
+
+  int_type underflow()
+  {
+    underflow_called = true;
+    return std::filebuf::underflow();
+  }
+
+  int_type uflow()
+  {
+    uflow_called = true;
+    return std::filebuf::uflow();
+  }
+};
+
+void test_05()
+{
+  bool test __attribute__((unused)) = true;
+
+  Close_filebuf fb_01, fb_02;
+  char buffer[] = "xxxxxxxxxx";
+
+  // 'in'
+  fb_01.open(name_01, std::ios_base::in);
+  fb_01.sgetc();
+
+  fb_01.close();
+
+  underflow_called = false;
+  fb_01.sgetc();
+  VERIFY( underflow_called == true );
+
+  uflow_called = false;
+  fb_01.sbumpc();
+  VERIFY( uflow_called == true );
+
+  uflow_called = false;
+  fb_01.snextc();
+  VERIFY( uflow_called == true );
+ 
+  uflow_called = false;
+  fb_01.sgetn(buffer, sizeof(buffer));
+  VERIFY( uflow_called == true );
+
+  // 'out'
+  fb_02.open(name_02, std::ios_base::out);
+
+  fb_02.close();
+
+  overflow_called = false;
+  fb_02.sputc('T');
+  VERIFY( overflow_called == true );
+
+  overflow_called = false;
+  fb_02.sputn(buffer, sizeof(buffer));
+  VERIFY( overflow_called == true );
+}
+
+int
+main()
+{
+  test_05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/9964.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/9964.cc
new file mode 100644
index 000000000..f2c5abc3e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/char/9964.cc
@@ -0,0 +1,89 @@
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+#include <fstream>
+#include <cstdlib>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+// No asserts, avoid leaking the semaphores if a VERIFY fails.
+#undef _GLIBCXX_ASSERT
+
+#include <testsuite_hooks.h>
+
+// libstdc++/9964
+bool test_07()
+{
+  using namespace std;
+  using namespace __gnu_test;
+  bool test __attribute__((unused)) = true;
+  semaphore s1, s2;
+
+  const char* name = "tmp_fifo3";
+
+  signal(SIGPIPE, SIG_IGN);
+
+  unlink(name);  
+  mkfifo(name, S_IRWXU);
+  
+  int child = fork();
+  VERIFY( child != -1 );
+
+  if (child == 0)
+    {
+      filebuf fbin;
+      fbin.open(name, ios_base::in);
+      s1.wait();
+      fbin.close();
+      s2.signal();
+      exit(0);
+    }
+  
+  filebuf fb;
+  filebuf* ret = fb.open(name, ios_base::in | ios_base::out);
+  VERIFY( ret != 0 );
+  VERIFY( fb.is_open() );
+  s1.signal();
+  s2.wait();
+  fb.sputc('a');
+
+  ret = fb.close();
+  VERIFY( ret != 0 );
+  VERIFY( !fb.is_open() );
+
+  return test;
+}
+
+int
+main()
+{
+  return !test_07();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-1.cc
new file mode 100644
index 000000000..85222f596
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-1.cc
@@ -0,0 +1,78 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(L'a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.close();
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-2.cc
new file mode 100644
index 000000000..eeade5812
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-2.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(L'a');
+  fb.in_avail(); // showmanyc() should have no effect on close().
+
+  VERIFY( !cvt->unshift_called );
+  fb.close();
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-3.cc
new file mode 100644
index 000000000..417fbc2ce
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-3.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return codecvt_base::error;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should fail if codecvt::unshift() fails
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+
+  VERIFY( !cvt->unshift_called );
+  wfilebuf* ret = fb.close();
+  VERIFY( cvt->unshift_called );
+  VERIFY( !ret );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-4.cc
new file mode 100644
index 000000000..240417a93
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/close/wchar_t/12790-4.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::close() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_close_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(L'a');
+  fb.pubsync(); // Does not call unshift()
+
+  VERIFY( !cvt->unshift_called );
+  fb.close();
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/2020.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/2020.cc
new file mode 100644
index 000000000..377e519a5
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/2020.cc
@@ -0,0 +1,52 @@
+// 1999-01-17 bkoz test functionality of basic_filebuf for char_type == char
+
+// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.1 - Template class basic_filebuf 
+// NB: This file is for testing basic_filebuf with NO OTHER INCLUDES.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/2020
+// should be able to use custom char_type, custom traits type
+void test07()
+{
+  bool test __attribute__((unused)) = true;
+  typedef std::basic_filebuf<__gnu_test::pod_ushort> gnu_filebuf;
+  
+  try
+    { gnu_filebuf obj; }
+  catch(std::exception& obj)
+    { 
+      test = false; 
+      VERIFY( test );
+    }
+}
+
+int main() 
+{
+  test07();
+  return 0;
+}
+
+
+
+// more surf!!!
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/char/1.cc
new file mode 100644
index 000000000..ab2e2c70f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/char/1.cc
@@ -0,0 +1,39 @@
+// 2004-09-29  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.2  basic_filebuf constructors  [lib.filebuf.cons]
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// http://gcc.gnu.org/ml/libstdc++/2004-09/msg00243.html
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  __gnu_test::constraint_filebuf fbuf;
+  VERIFY( fbuf.check_pointers() );
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/wchar_t/1.cc
new file mode 100644
index 000000000..e2081de7c
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/wchar_t/1.cc
@@ -0,0 +1,39 @@
+// 2004-09-29  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.2  basic_filebuf constructors  [lib.filebuf.cons]
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// http://gcc.gnu.org/ml/libstdc++/2004-09/msg00243.html
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  __gnu_test::constraint_wfilebuf fbuf;
+  VERIFY( fbuf.check_pointers() );
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/wchar_t/10132-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/wchar_t/10132-1.cc
new file mode 100644
index 000000000..69d2d4517
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/cons/wchar_t/10132-1.cc
@@ -0,0 +1,52 @@
+// 2003-04-24 Pétur Runólfsson <peturr02@ru.is>
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <fstream>
+#include <locale>
+#include <stdexcept>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+protected:
+  virtual std::codecvt_base::result
+  do_out(std::mbstate_t&, const wchar_t*, const wchar_t*, const wchar_t*&, 
+	 char*, char*, char*&) const
+  { throw std::runtime_error("codecvt failed"); }
+};
+
+int main()
+{
+  bool test __attribute__((unused)) = true;
+
+  std::locale loc = std::locale(std::locale::classic(), new Cvt);
+  std::wfilebuf* fb = new std::wfilebuf;
+  fb->pubimbue(loc);
+  fb->open("tmp_10132", std::ios_base::out);
+  fb->sputc(L'a');
+  
+  try
+    {
+      delete fb;
+    }
+  catch(std::exception& obj)
+    {
+      VERIFY( false ); 
+    }
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/12206.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/12206.cc
new file mode 100644
index 000000000..4c6bebf1f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/12206.cc
@@ -0,0 +1,125 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+
+typedef unsigned char Char;
+
+namespace std
+{
+  template <>
+  class codecvt<Char, char, mbstate_t> :
+    public locale::facet, public codecvt_base
+  {
+  public:
+    typedef Char intern_type;
+    typedef char extern_type;
+    typedef mbstate_t state_type;
+    
+    explicit codecvt(size_t refs = 0)
+      : locale::facet(refs) { }
+    result out(mbstate_t& state, const Char* from,
+	       const Char* from_end, const Char*& from_next,
+	       char* to, char* to_limit, char*& to_next) const
+    {
+      return do_out(state, from, from_end, from_next,
+		    to, to_limit, to_next);
+    }
+    result in(mbstate_t& state, const char* from,
+	      const char* from_end, const char*& from_next,
+	      Char* to, Char* to_limit, Char*& to_next) const
+    {
+      return do_in(state, from, from_end, from_next,
+		   to, to_limit, to_next);
+    }
+    result unshift(mbstate_t& state, char* to, char* to_end,
+		   char*& to_next) const
+    { return do_unshift(state, to, to_end, to_next); }
+    int length(mbstate_t& state, const char* from,
+	       const char* from_end, size_t max) const
+    { return do_length(state, from, from_end, max); }
+    int encoding() const throw()
+    { return do_encoding(); }
+    bool always_noconv() const throw()
+    { return do_always_noconv(); }
+    int max_length() const throw()
+    { return do_max_length(); }
+    
+    static locale::id id;
+    
+  protected:
+    virtual result do_out(mbstate_t&, const Char*,
+			  const Char*,
+			  const Char*&, char*,
+			  char*, char*&) const
+    { return ok; }
+    virtual result do_in(mbstate_t&, const char*,
+			 const char*,
+			 const char*&, Char*,
+			 Char*, Char*&) const
+    { return ok; }
+    virtual result do_unshift(mbstate_t&, char*, char*,
+			      char*&) const
+    { return noconv; }
+    virtual int do_length(mbstate_t&, const char*,
+			  const char*, size_t) const
+    { return 1; }
+    virtual int do_encoding() const throw()
+    { return 1; }
+    virtual bool do_always_noconv() const throw()
+    { return false; }
+    virtual int do_max_length() const throw()
+    { return 1; }
+  };
+  
+  locale::id codecvt<Char, char, mbstate_t>::id;
+}
+
+// libstdc++/12206
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  
+  locale loc(locale::classic(),
+	     new codecvt<Char, char, std::mbstate_t>);
+  locale::global(loc);
+  
+  basic_filebuf<Char, char_traits<Char> > fb;
+
+  loc = locale::classic();
+  locale::global(loc);
+  fb.pubimbue(loc);
+
+  fb.open("tmp_12206", ios_base::out);
+  try
+    {
+      fb.pubseekoff(0, ios_base::cur);
+    }
+  catch (std::exception&)
+    {
+    }
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/1.cc
new file mode 100644
index 000000000..37bc1a555
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/1.cc
@@ -0,0 +1,44 @@
+// 981208 bkoz test functionality of basic_stringbuf for char_type == char
+
+// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+std::filebuf fbuf;
+
+// test the filebuf locale settings
+void test02() 
+{
+  std::locale loc_c = std::locale::classic();
+  loc_c = fbuf.getloc();
+  fbuf.pubimbue(loc_c); //This should initialize _M_init to true
+  std::locale loc_tmp = fbuf.getloc(); 
+  VERIFY( loc_tmp == loc_c );
+}
+
+int main()
+{
+  test02();
+  return 0;
+}
+
+
+
+// more candy!!!
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13007.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13007.cc
new file mode 100644
index 000000000..326aa1fd8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13007.cc
@@ -0,0 +1,62 @@
+// { dg-require-namedlocale "fr_FR" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+class Buf : public std::filebuf
+{
+public:
+  std::locale before;
+  std::locale after;
+
+protected:
+  void imbue(const std::locale& loc)
+  {
+    before = getloc();
+
+    std::filebuf::imbue(loc);
+
+    after = getloc();
+  }
+};
+
+// libstdc++/13007
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  Buf buf;
+  std::locale loc(std::locale("fr_FR"));
+
+  buf.pubimbue(loc);
+
+  VERIFY( buf.getloc() == loc );
+  VERIFY( buf.before == std::locale::classic() );
+  VERIFY( buf.after == std::locale::classic() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-1.cc
new file mode 100644
index 000000000..9fbf67aef
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-1.cc
@@ -0,0 +1,46 @@
+// { dg-require-namedlocale "en_US" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+// libstdc++/13171
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  filebuf fb;
+  
+  fb.pubimbue(locale("en_US"));
+  fb.pubimbue(locale("en_US"));
+  
+  fb.open("tmp_13171-1", ios_base::out);
+  fb.sputc('F');
+  fb.pubsync();
+  fb.close();
+}
+
+int main()
+{
+  test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-2.cc
new file mode 100644
index 000000000..fa0bf15c0
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-2.cc
@@ -0,0 +1,83 @@
+// { dg-require-namedlocale "fr_FR" }
+// { dg-require-namedlocale "en_US" }
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdlib>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+// No asserts, avoid leaking the semaphores if a VERIFY fails.
+#undef _GLIBCXX_ASSERT
+
+#include <testsuite_hooks.h>
+
+// libstdc++/13171
+bool test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  using namespace __gnu_test;
+
+  locale loc_fr(locale("fr_FR"));
+  locale loc_en(locale("en_US"));
+
+  const char* name = "tmp_fifo_13171-2";
+  unlink(name);
+  mkfifo(name, S_IRWXU);
+  semaphore s1, s2;
+  
+  int child = fork();
+  if (child == 0)
+    {
+      filebuf fb;
+      fb.open(name, ios_base::out);
+      fb.sputc('S');
+      fb.pubsync();
+      s1.signal();
+      s2.wait();
+      fb.close();
+      exit(0);
+    }
+
+  filebuf fb;
+  fb.pubimbue(loc_fr);
+  fb.open(name, ios_base::in);
+  s1.wait();
+  VERIFY( fb.is_open() );
+  fb.pubimbue(loc_en);
+  filebuf::int_type c = fb.sgetc();
+  fb.close();
+  VERIFY( c == 'S' );
+  s2.signal();
+
+  return test;
+}
+
+int main()
+{
+  return !test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-4.cc
new file mode 100644
index 000000000..1ac9557ce
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13171-4.cc
@@ -0,0 +1,56 @@
+// { dg-require-namedlocale "en_US" }
+// { dg-require-namedlocale "fr_FR" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+protected:
+  int do_encoding() const throw()
+  { return -1; }
+
+  bool do_always_noconv() const throw()
+  { return false; }
+};
+
+// libstdc++/13171
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  filebuf fb;
+  fb.pubimbue(locale(locale("en_US"), new Cvt));
+  fb.open("tmp_13171-4", ios_base::out);
+  fb.pubimbue(locale("fr_FR"));
+  fb.sputc('N');
+  fb.pubsync();
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13582-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13582-2.cc
new file mode 100644
index 000000000..fdcc03022
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/13582-2.cc
@@ -0,0 +1,84 @@
+// { dg-require-namedlocale "en_US" }
+// { dg-require-namedlocale "fr_FR" }
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// 2004-01-11  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2004, 2005, 2006, 2007, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdlib>
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <testsuite_hooks.h>
+
+// libstdc++/13582
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std; 
+  using namespace __gnu_test;
+
+  locale loc_en(locale("en_US"));
+  locale loc_fr(locale("fr_FR"));
+
+  const char* name = "tmp_fifo_13582-2";
+  unlink(name);
+  mkfifo(name, S_IRWXU);
+
+  int child = fork();
+  if (child == 0)
+    {
+      filebuf fbout;
+      fbout.open(name, ios_base::out);
+      fbout.sputn("12345", 5);
+      fbout.pubsync();
+      fbout.close();
+      exit(0);
+    }
+
+  filebuf fbin;
+  fbin.open(name, ios_base::in);
+  filebuf::int_type n = fbin.sbumpc();
+  VERIFY( n == '1' );
+  fbin.pubimbue(loc_en);
+  n = fbin.sbumpc();
+  VERIFY( n == '2' );
+  fbin.pubimbue(loc_fr);
+  n = fbin.sbumpc();
+  VERIFY( n == '3' );
+  n = fbin.sbumpc();
+  VERIFY( n == '4' );
+  n = fbin.sbumpc();
+  VERIFY( n == '5' );
+  n = fbin.sbumpc();
+  VERIFY( n == filebuf::traits_type::eof() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/14975-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/14975-1.cc
new file mode 100644
index 000000000..5007b085e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/14975-1.cc
@@ -0,0 +1,68 @@
+// { dg-require-namedlocale "en_US" }
+
+// 2004-04-16  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2004, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+class Buf : public std::filebuf
+{
+protected:
+  virtual int_type
+  overflow(int_type c = traits_type::eof())
+  {
+    return traits_type::eq_int_type(c, traits_type::eof()) ?
+      traits_type::eof() : std::filebuf::overflow(c);
+  }
+};
+
+// libstdc++/14975
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  Buf fb;
+  locale loc_us = locale("en_US");
+  fb.pubimbue(loc_us);
+  fb.open("tmp_14975-1", ios_base::out);
+  
+  try
+    {
+      fb.sputc('a');
+      fb.sputc('b');
+      fb.pubimbue(locale::classic());
+      fb.sputc('c');
+      fb.pubsync();
+      fb.close();
+    }
+  catch (std::exception&)
+    {
+    }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/2.cc
new file mode 100644
index 000000000..f4d574c21
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/2.cc
@@ -0,0 +1,55 @@
+// { dg-require-namedlocale "de_DE" }
+
+// 2003-05-13 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+void test02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+  locale loc;
+  filebuf ob;
+  VERIFY( ob.getloc() == loc );
+  ob.open(name_01, ios_base::in);
+  VERIFY( ob.is_open() );
+ 
+  typedef streambuf::pos_type pos_type;
+  pos_type bad = pos_type(streambuf::off_type(-1));
+  pos_type p = ob.pubseekoff(2, ios_base::beg, ios_base::in);
+  VERIFY( p != bad);
+
+  // According to 27.5.2.2.1, loc == getloc() after pubimbue(loc).
+  locale loc_de = locale("de_DE");
+  locale ret = ob.pubimbue(loc_de);
+  VERIFY( ob.getloc() == loc_de );
+}
+
+int main() 
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/3.cc
new file mode 100644
index 000000000..055573b96
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/3.cc
@@ -0,0 +1,55 @@
+// 2003-05-13 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+class state_codecvt : public std::codecvt<char, char, std::mbstate_t>
+{
+protected:
+  int
+  do_encoding() const throw()
+  { return -1; }
+};
+
+void test03()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc_s(locale::classic(), new state_codecvt);
+  filebuf ob;
+  ob.pubimbue(loc_s);
+  VERIFY( ob.getloc() == loc_s );
+
+  // 2 "if encoding of current locale is state dependent" and
+  // not at the beginning of the file fails...
+  locale loc_c = locale::classic();
+  locale ret = ob.pubimbue(loc_s);
+  VERIFY( ob.getloc() == loc_s );
+}
+
+int main() 
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/9322.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/9322.cc
new file mode 100644
index 000000000..8a611e0dc
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/char/9322.cc
@@ -0,0 +1,55 @@
+// { dg-require-namedlocale "en_US" }
+// { dg-require-namedlocale "de_DE" }
+
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+// libstdc++/9322
+void test07()
+{
+  using std::locale;
+  bool test __attribute__((unused)) = true;
+
+  locale loc;
+  std::filebuf ob;
+  VERIFY( ob.getloc() == loc );
+
+  locale::global(locale("en_US"));
+  VERIFY( ob.getloc() == loc );
+
+  locale loc_de = locale("de_DE");
+  locale ret = ob.pubimbue(loc_de);
+  VERIFY( ob.getloc() == loc_de );
+  VERIFY( ret == loc );
+
+  locale::global(loc);
+  VERIFY( ob.getloc() == loc_de );
+}
+
+int main() 
+{
+  test07();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/1.cc
new file mode 100644
index 000000000..f5c6daac3
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/1.cc
@@ -0,0 +1,44 @@
+// 981208 bkoz test functionality of basic_stringbuf for char_type == char
+
+// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+std::wfilebuf fbuf;
+
+// test the filebuf locale settings
+void test02() 
+{
+  std::locale loc_c = std::locale::classic();
+  loc_c = fbuf.getloc();
+  fbuf.pubimbue(loc_c); //This should initialize _M_init to true
+  std::locale loc_tmp = fbuf.getloc(); 
+  VERIFY( loc_tmp == loc_c );
+}
+
+int main()
+{
+  test02();
+  return 0;
+}
+
+
+
+// more candy!!!
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/12868.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/12868.cc
new file mode 100644
index 000000000..bc7c3c1bd
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/12868.cc
@@ -0,0 +1,61 @@
+// { dg-require-namedlocale "is_IS.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <ostream>
+#include <fstream>
+#include <locale>
+#include <string>
+#include <testsuite_hooks.h>
+
+// libstdc++/12868
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc_is(locale("is_IS.UTF-8"));
+  
+  {
+    wofstream out("tmp_12868");
+    out << L"<? xml version=\"1.0\" encoding=\"UTF-8\" ?>\n";
+    out.imbue(loc_is);
+    VERIFY( out.rdbuf()->getloc() == loc_is );
+    out << L"<greeting>Hall\u00f3 heimur</greeting>\n";
+  }
+
+  {
+    wifstream in("tmp_12868");
+    wstring str;
+    getline(in, str);
+    if (str.find(L"encoding=\"UTF-8\"") != wstring::npos)
+      {
+	in.imbue(loc_is);
+	VERIFY( in.rdbuf()->getloc() == loc_is );
+      }
+    getline(in, str);
+    VERIFY( str == L"<greeting>Hall\u00f3 heimur</greeting>" );
+  }
+}
+
+int main()
+{
+  test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13007.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13007.cc
new file mode 100644
index 000000000..9bb1f4035
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13007.cc
@@ -0,0 +1,62 @@
+// { dg-require-namedlocale "fr_FR" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+class Buf : public std::wfilebuf
+{
+public:
+  std::locale before;
+  std::locale after;
+
+protected:
+  void imbue(const std::locale& loc)
+  {
+    before = getloc();
+
+    std::wfilebuf::imbue(loc);
+
+    after = getloc();
+  }
+};
+
+// libstdc++/13007
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  Buf buf;
+  std::locale loc(std::locale("fr_FR"));
+
+  buf.pubimbue(loc);
+
+  VERIFY( buf.getloc() == loc );
+  VERIFY( buf.before == std::locale::classic() );
+  VERIFY( buf.after == std::locale::classic() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13171-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13171-3.cc
new file mode 100644
index 000000000..ec11237d0
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13171-3.cc
@@ -0,0 +1,59 @@
+// { dg-require-namedlocale "fr_FR" }
+// { dg-require-namedlocale "en_US" }
+// { dg-require-namedlocale "de_DE" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <iostream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+// libstdc++/13171
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  locale::global(locale("fr_FR"));
+
+  ios_base::sync_with_stdio(false);
+
+  locale::global(locale("en_US"));
+  cin.imbue(locale("en_US"));
+  cout.imbue(locale("en_US"));
+  cerr.imbue(locale("en_US"));
+  clog.imbue(locale("de_DE"));
+  wcin.imbue(locale("en_US"));
+  wcout.imbue(locale("en_US"));
+  wcerr.imbue(locale("en_US"));
+  wclog.imbue(locale("de_DE"));
+ 
+  cout << 'f' << endl;
+  cerr << 'r' << endl;
+  clog << 'A' << endl;
+  wcout << L's' << endl;
+  wcerr << L'i' << endl;
+  wclog << L'L' << endl;
+}
+
+int main()
+{
+  test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13582-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13582-2.cc
new file mode 100644
index 000000000..7a997739f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13582-2.cc
@@ -0,0 +1,86 @@
+// { dg-require-namedlocale "en_US" }
+// { dg-require-namedlocale "fr_FR" }
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// 2004-01-11  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2004, 2005, 2006, 2007, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdlib>
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <testsuite_hooks.h>
+
+// libstdc++/13582
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  using namespace __gnu_test;
+
+  locale loc_en(locale("en_US"));
+  locale loc_fr(locale("fr_FR"));
+
+  const char* name = "tmp_fifo_13582-2";
+  unlink(name);
+  mkfifo(name, S_IRWXU);
+  
+  int child = fork();
+  if (child == 0)
+    {
+      filebuf fbout;
+      fbout.open(name, ios_base::out);
+      fbout.sputn("12345", 5);
+      fbout.pubsync();
+      sleep(2);
+      fbout.close();
+      exit(0);
+    }
+
+  wfilebuf fbin;
+  fbin.open(name, ios_base::in);
+  sleep(1);
+  wfilebuf::int_type n = fbin.sbumpc();
+  VERIFY( n == L'1' );
+  fbin.pubimbue(loc_en);
+  n = fbin.sbumpc();
+  VERIFY( n == L'2' );
+  fbin.pubimbue(loc_fr);
+  n = fbin.sbumpc();
+  VERIFY( n == L'3' );
+  n = fbin.sbumpc();
+  VERIFY( n == L'4' );
+  n = fbin.sbumpc();
+  VERIFY( n == L'5' );
+  n = fbin.sbumpc();
+  VERIFY( n == wfilebuf::traits_type::eof() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13582-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13582-3.cc
new file mode 100644
index 000000000..246ae8c6e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/13582-3.cc
@@ -0,0 +1,74 @@
+// { dg-require-namedlocale "en_US" }
+// { dg-require-namedlocale "fr_FR" }
+
+// 2004-01-11  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2004, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+// libstdc++/13582
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  locale loc_en(locale("en_US"));
+  locale loc_fr(locale("fr_FR"));
+
+  const char* name = "tmp_13582-3.tst";
+
+  {
+    filebuf fbout;
+    fbout.open(name, ios_base::out);
+    fbout.sputn("AbCdE", 5);
+    fbout.close();
+  }
+
+  {
+    wfilebuf fbin;
+    fbin.open(name, ios_base::in);
+    wfilebuf::int_type n = fbin.sbumpc();
+    VERIFY( n == L'A' );
+    fbin.pubimbue(loc_en);
+    fbin.pubseekoff(0, ios_base::cur);
+    n = fbin.sbumpc();
+    VERIFY( n == L'b' );
+    fbin.pubimbue(loc_fr);
+    n = fbin.sbumpc();
+    VERIFY( n == L'C' );
+    n = fbin.sbumpc();
+    VERIFY( n == L'd' );
+    fbin.pubseekoff(0, ios_base::cur);
+    n = fbin.sbumpc();
+    VERIFY( n == L'E' );
+    n = fbin.sbumpc();
+    VERIFY( n == wfilebuf::traits_type::eof() );
+    fbin.close();
+  }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/14975-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/14975-2.cc
new file mode 100644
index 000000000..dc1314556
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/14975-2.cc
@@ -0,0 +1,95 @@
+// { dg-require-namedlocale "en_US" }
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// 2004-04-16  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <fstream>
+#include <locale>
+#include <cstdlib>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+// No asserts, avoid leaking the semaphore if a VERIFY fails.
+#undef _GLIBCXX_ASSERT
+
+#include <testsuite_hooks.h>
+
+// libstdc++/14975
+bool test01()
+{
+  using namespace std;
+  using namespace __gnu_test;
+  bool test __attribute__((unused)) = true;
+
+  locale loc_us = locale("en_US");
+
+  const char* name = "tmp_14975-2";
+
+  signal(SIGPIPE, SIG_IGN);
+
+  unlink(name);  
+  mkfifo(name, S_IRWXU);
+  semaphore s1;
+
+  int child = fork();
+  VERIFY( child != -1 );
+
+  if (child == 0)
+    {
+      {
+	filebuf fbin;
+	fbin.open(name, ios_base::in);
+      }
+      s1.signal();
+      exit(0);
+    }
+  
+  wfilebuf fb;
+  fb.pubimbue(loc_us);
+  wfilebuf* ret = fb.open(name, ios_base::out);
+  VERIFY( ret != 0 );
+  VERIFY( fb.is_open() );
+
+  s1.wait();
+
+  try
+    {
+      fb.sputc(L'a');
+      fb.sputc(L'b');
+      fb.pubimbue(locale::classic());
+      fb.sputc(L'c');
+      fb.close();
+    }
+  catch (std::exception&)
+    {
+    }
+
+  return test;
+}
+
+int main()
+{
+  return !test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/2.cc
new file mode 100644
index 000000000..52941a5fc
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/2.cc
@@ -0,0 +1,55 @@
+// { dg-require-namedlocale "de_DE" }
+
+// 2003-05-13 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+void test02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+  locale loc;
+  wfilebuf ob;
+  VERIFY( ob.getloc() == loc );
+  ob.open(name_01, ios_base::in);
+  VERIFY( ob.is_open() );
+ 
+  typedef streambuf::pos_type pos_type;
+  pos_type bad = pos_type(streambuf::off_type(-1));
+  pos_type p = ob.pubseekoff(2, ios_base::beg, ios_base::in);
+  VERIFY( p != bad);
+
+  // According to 27.5.2.2.1, p1, loc == getloc() after pubimbue(loc).
+  locale loc_de = locale("de_DE");
+  locale ret = ob.pubimbue(loc_de);
+  VERIFY( ob.getloc() == loc_de );
+}
+
+int main() 
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/3.cc
new file mode 100644
index 000000000..01baec6b5
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/3.cc
@@ -0,0 +1,55 @@
+// 2003-05-13 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+class state_codecvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+protected:
+  int
+  do_encoding() const throw()
+  { return -1; }
+};
+
+void test03()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc_s(locale::classic(), new state_codecvt);
+  wfilebuf ob;
+  ob.pubimbue(loc_s);
+  VERIFY( ob.getloc() == loc_s );
+
+  // 2 "if encoding of current locale is state dependent" and
+  // not at the beginning of the file fails...
+  locale loc_c = locale::classic();
+  locale ret = ob.pubimbue(loc_s);
+  VERIFY( ob.getloc() == loc_s );
+}
+
+int main() 
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/9322.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/9322.cc
new file mode 100644
index 000000000..f69d9f0d6
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/imbue/wchar_t/9322.cc
@@ -0,0 +1,55 @@
+// { dg-require-namedlocale "en_US" }
+// { dg-require-namedlocale "de_DE" }
+
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+// libstdc++/9322
+void test07()
+{
+  using std::locale;
+  bool test __attribute__((unused)) = true;
+
+  locale loc;
+  std::wfilebuf ob;
+  VERIFY( ob.getloc() == loc );
+
+  locale::global(locale("en_US"));
+  VERIFY( ob.getloc() == loc );
+
+  locale loc_de = locale("de_DE");
+  locale ret = ob.pubimbue(loc_de);
+  VERIFY( ob.getloc() == loc_de );
+  VERIFY( ret == loc );
+
+  locale::global(loc);
+  VERIFY( ob.getloc() == loc_de );
+}
+
+int main() 
+{
+  test07();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/in_avail/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/in_avail/char/1.cc
new file mode 100644
index 000000000..94b331867
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/in_avail/char/1.cc
@@ -0,0 +1,100 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+// NB: This test assumes that _M_buf_size == 40, and not the usual
+// buffer_size length of BUFSIZ (8192), so that overflow/underflow can be
+// simulated a bit more readily.
+// NRB (Nota Really Bene): setting it to 40 breaks the test, as intended.
+const int buffer_size = 8192;
+//const int buffer_size = 40;
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_02[] = "filebuf_virtuals-2.txt"; // empty file, need to create
+const char name_03[] = "filebuf_virtuals-3.txt"; // empty file, need to create
+
+class derived_filebuf: public std::filebuf
+{
+ public:
+  void
+  set_size(int_type __size) { _M_buf_size = __size; }
+};
+
+derived_filebuf fb_01; // in 
+derived_filebuf fb_02; // out
+derived_filebuf fb_03; // in | out
+
+// Initialize filebufs to be the same size regardless of platform.
+void test03()
+{
+  fb_01.set_size(buffer_size);
+  fb_02.set_size(buffer_size);
+  fb_03.set_size(buffer_size);
+}
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  typedef std::filebuf::int_type 	int_type;
+  typedef std::filebuf::traits_type 	traits_type;
+  typedef std::filebuf::pos_type 	pos_type;
+  typedef std::filebuf::off_type 	off_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  std::filebuf 				f_tmp;
+  std::streamoff  			strmof_1, strmof_2;
+
+  // GET
+  // int in_avail()
+  // if a read position is available, return _M_in_end - _M_in_cur.
+  // else return showmanyc.
+  strmof_1 = fb_01.in_avail();
+  strmof_2 = fb_02.in_avail();
+  VERIFY( strmof_1 == -1 );
+  VERIFY( strmof_1 == strmof_2 ); //fail because not open
+  strmof_1 = fb_03.in_avail();
+  VERIFY( strmof_1 == strmof_2 );
+  fb_01.open(name_01, std::ios_base::in);
+  fb_02.open(name_02, std::ios_base::out | std::ios_base::trunc);
+  fb_03.open(name_03, std::ios_base::out | std::ios_base::in | std::ios_base::trunc); 
+  strmof_1 = fb_01.in_avail();
+  strmof_2 = fb_02.in_avail();
+  VERIFY( strmof_1 != strmof_2 );
+  VERIFY( strmof_1 >= 0 );
+  VERIFY( strmof_2 == -1 );  // empty file
+  strmof_1 = fb_03.in_avail(); 
+  VERIFY( strmof_1  == 0 ); // empty file
+}
+
+int main() 
+{
+  test03();
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/in_avail/char/9701-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/in_avail/char/9701-3.cc
new file mode 100644
index 000000000..b68f65647
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/in_avail/char/9701-3.cc
@@ -0,0 +1,60 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.5.2.2.3 Get area
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Derived_fbuf : public std::filebuf
+{
+public:
+  const char_type* pub_egptr() const
+  { return egptr(); }
+
+  const char_type* pub_gptr() const
+  { return gptr(); }
+};
+
+// libstdc++/9701 (in_avail)
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_file1";
+
+  Derived_fbuf df2;
+  df2.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+
+  df2.sputn("Comomoc", 7);
+
+  df2.pubseekoff(0, ios_base::beg);
+  df2.sbumpc();
+  df2.sputbackc('t');
+
+  VERIFY( df2.pub_gptr() < df2.pub_egptr() );
+  VERIFY( df2.in_avail() == df2.pub_egptr() - df2.pub_gptr() );
+}
+
+int
+main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/is_open/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/is_open/char/1.cc
new file mode 100644
index 000000000..1b5a66ea8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/is_open/char/1.cc
@@ -0,0 +1,73 @@
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_members-1.tst";
+const char name_02[] = "filebuf_members-1.txt";
+
+// Test member functions.
+void test_01() 
+{
+  bool test __attribute__((unused)) = true;
+  const char* name_03 = "filebuf_members-3"; // empty file, need to create
+
+  std::filebuf fb_01; // in 
+  std::filebuf fb_02; // out
+  std::filebuf fb_03; // in | out
+
+  // bool is_open()
+  VERIFY( !fb_01.is_open() );
+  VERIFY( !fb_02.is_open() );
+  VERIFY( !fb_03.is_open() );
+
+  // filebuf_type* open(const char* __s, ios_base::openmode __mode)
+  fb_01.open(name_01, std::ios_base::in | std::ios_base::ate);
+  fb_02.open(name_02, std::ios_base::in | std::ios_base::out 
+	     | std::ios_base::trunc);
+  fb_03.open(name_03, std::ios_base::out | std::ios_base::trunc);
+  VERIFY( fb_01.is_open() );
+  VERIFY( fb_02.is_open() );
+  VERIFY( fb_03.is_open() );
+
+  // filebuf_type* close()
+  fb_01.close();
+  fb_02.close();
+  fb_03.close();
+  VERIFY( !fb_01.is_open() );
+  VERIFY( !fb_02.is_open() );
+  VERIFY( !fb_03.is_open() );
+}
+
+int
+main()
+{
+  test_01();
+  return 0;
+}
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/open/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/12790-1.cc
new file mode 100644
index 000000000..fc69cd4eb
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/12790-1.cc
@@ -0,0 +1,61 @@
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_open_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(pod_uchar::from<char>('b'));
+  fb.close();
+
+  // Check that reopened basic_filebuf begins in the initial state.
+  fb.open(name, ios_base::in);
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('b')) );
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/1.cc
new file mode 100644
index 000000000..1a40da155
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/1.cc
@@ -0,0 +1,74 @@
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_members-1.tst";
+const char name_02[] = "filebuf_members-1.txt";
+
+// Test member functions.
+void test_01() 
+{
+  bool test __attribute__((unused)) = true;
+  const char* name_03 = "filebuf_members-3"; // empty file, need to create
+
+  std::filebuf fb_01; // in 
+  std::filebuf fb_02; // out
+  std::filebuf fb_03; // in | out
+
+  // bool is_open()
+  VERIFY( !fb_01.is_open() );
+  VERIFY( !fb_02.is_open() );
+  VERIFY( !fb_03.is_open() );
+
+  // filebuf_type* open(const char* __s, ios_base::openmode __mode)
+  fb_01.open(name_01, std::ios_base::in | std::ios_base::ate);
+  VERIFY( fb_01.is_open() );
+
+  // Try to open two different files without closing the first:
+  // Should keep the old file attached, and disregard attempt to overthrow.
+  std::filebuf* f = fb_02.open(name_02, std::ios_base::in | std::ios_base::out 
+			       | std::ios_base::trunc);
+  VERIFY( f );
+  VERIFY( fb_02.is_open() );
+  
+  f = fb_02.open(name_03, std::ios_base::in | std::ios_base::out);
+  VERIFY( !f );
+  VERIFY( fb_02.is_open() );
+
+  fb_03.open(name_03, std::ios_base::out | std::ios_base::trunc);
+  VERIFY( fb_03.is_open() );
+}
+
+int
+main()
+{
+  test_01();
+  return 0;
+}
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/2.cc
new file mode 100644
index 000000000..755784fb9
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/2.cc
@@ -0,0 +1,59 @@
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <ext/stdio_filebuf.h>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+void test_03()
+{
+  bool test __attribute__((unused)) = true;
+  int first_fd = ::open(name_01, O_RDONLY);
+  VERIFY( first_fd != -1 );
+  FILE* first_file = ::fdopen(first_fd, "r");
+  VERIFY( first_file );
+  __gnu_cxx::stdio_filebuf<char> fb(first_file, std::ios_base::in);
+
+  int second_fd = fb.fd();
+
+  VERIFY( first_fd == second_fd );
+}
+
+int
+main()
+{
+  test_03();
+  return 0;
+}
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/3.cc
new file mode 100644
index 000000000..6b076a699
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/3.cc
@@ -0,0 +1,54 @@
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+// Charles Leggett <CGLeggett@lbl.gov>
+void test_05()
+{
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_file5";
+
+  std::fstream scratch_file;
+
+  scratch_file.open(name, std::ios::out);
+  scratch_file.close();
+
+  scratch_file.open(name, std::ios::in);
+  if (!scratch_file)
+    VERIFY( false );
+  scratch_file.close();
+}
+
+int
+main()
+{
+  test_05();
+  return 0;
+}
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/4.cc
new file mode 100644
index 000000000..31d25422b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/4.cc
@@ -0,0 +1,72 @@
+// 2006-10-01  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2006, 2007, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+// DR 596.
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_file4";
+
+  std::fstream scratch_file;
+
+  scratch_file.open(name, std::ios_base::app);
+  VERIFY( scratch_file );
+  VERIFY( scratch_file.is_open() );
+  scratch_file.close();
+
+  scratch_file.open(name, std::ios_base::in | std::ios_base::out
+		    | std::ios_base::app);
+  VERIFY( scratch_file );
+  VERIFY( scratch_file.is_open() );
+  scratch_file.close();
+
+  scratch_file.open(name, std::ios_base::in | std::ios_base::app);
+  VERIFY( scratch_file );
+  VERIFY( scratch_file.is_open() );
+  scratch_file.close();
+
+  scratch_file.open(name, std::ios_base::app | std::ios_base::binary);
+  VERIFY( scratch_file );
+  VERIFY( scratch_file.is_open() );
+  scratch_file.close();
+
+  scratch_file.open(name, std::ios_base::in | std::ios_base::out
+		    | std::ios_base::app | std::ios_base::binary);
+  VERIFY( scratch_file );
+  VERIFY( scratch_file.is_open() );  
+  scratch_file.close();
+
+  scratch_file.open(name, std::ios_base::in | std::ios_base::app
+		    | std::ios_base::binary);
+  VERIFY( scratch_file );
+  VERIFY( scratch_file.is_open() );  
+  scratch_file.close();
+}
+
+int
+main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/5.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/5.cc
new file mode 100644
index 000000000..47721e6ad
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/5.cc
@@ -0,0 +1,30 @@
+// Copyright (C) 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-do compile }
+// { dg-options "-std=gnu++0x" }
+
+#include <fstream>
+
+// Test member functions.
+void test01()
+{
+  std::filebuf fb;
+
+  const std::string name = "filebuf_name.txt";
+  fb.open(name, std::ios_base::in | std::ios_base::ate);
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/9507.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/9507.cc
new file mode 100644
index 000000000..5b404375e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/open/char/9507.cc
@@ -0,0 +1,72 @@
+// { dg-require-mkfifo "" }
+
+// Copyright (C) 2001, 2002, 2003, 2005, 2009, 2010
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.3 filebuf member functions
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %-*.txt
+
+// various tests for filebuf::open() and filebuf::close() including
+// the non-portable functionality in the libstdc++-v3 IO library
+
+#include <fstream>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <testsuite_hooks.h>
+
+// libstdc++/9507
+void test_06()
+{
+  using namespace __gnu_test;
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_fifo2";
+
+  signal(SIGPIPE, SIG_IGN);
+
+  unlink(name);
+  mkfifo(name, S_IRWXU);
+  
+  std::filebuf fbuf;
+  // The use of ios_base::ate implies an attempt to seek on the file
+  // descriptor.  The seek will fail.  Thus, at the OS level, this
+  // call to "fbuf.open" will result in a call to "open" (which will
+  // succeed), a call to "lseek" (which will fail), and, finally, a
+  // call to "close" (which will succeed).  Thus, after this call, the
+  // file should be closed.
+  std::filebuf* r = fbuf.open(name,
+			      std::ios_base::in 
+			      | std::ios_base::out
+			      | std::ios_base::ate);
+  if (!r)
+    VERIFY( !fbuf.is_open() );
+  else
+    VERIFY( fbuf.is_open() );
+}
+
+int
+main()
+{
+  test_06();
+  return 0;
+}
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/1.cc
new file mode 100644
index 000000000..7c6874313
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/1.cc
@@ -0,0 +1,70 @@
+// 1999-10-11 bkoz
+
+// Copyright (C) 1999, 2000, 2001, 2002, 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+
+#include <fstream>
+#include <ostream>
+#include <testsuite_hooks.h>
+
+// test03
+// http://gcc.gnu.org/ml/libstdc++/2000-q1/msg00151.html
+template<typename charT, typename traits = std::char_traits<charT> >
+  class basic_nullbuf : public std::basic_filebuf<charT, traits>
+  {
+  protected:
+    typedef typename
+      std::basic_filebuf<charT, traits>::int_type int_type;
+    virtual int_type 
+    overflow(int_type c) 
+    {  return traits::not_eof(c); }
+  };
+
+typedef basic_nullbuf<char> nullbuf;
+
+template<typename T>
+  char
+  print(const T& x) 
+  {
+   nullbuf ob;
+   std::ostream out(&ob); 
+   out << x << std::endl;
+   return (!out ? '0' : '1');
+ }
+
+void test03() 
+{
+  bool test __attribute__((unused)) = true;
+  const std::string control01("11111");
+  std::string test01;
+
+  test01 += print(true);
+  test01 += print(3.14159);
+  test01 += print(10);
+  test01 += print('x');
+  test01 += print("pipo");
+
+  VERIFY( test01 == control01 );
+}
+
+int main() 
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/13858.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/13858.cc
new file mode 100644
index 000000000..27f7b3664
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/13858.cc
@@ -0,0 +1,69 @@
+// 2004-02-14  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+protected:
+  virtual std::codecvt_base::result
+  do_out(std::mbstate_t&, const char* from, const char*,
+	 const char*& from_next, char* to, char*, char*& to_next) const
+  {
+    from_next = from;
+    to_next = to;
+    return std::codecvt_base::error;
+  }
+
+  virtual bool
+  do_always_noconv() const throw()
+  { return false; }
+};
+
+// libstdc++/13858
+void test01()
+{
+  using namespace std;
+  
+  filebuf fb;
+  fb.pubimbue(locale(locale::classic(), new Cvt));
+  fb.open("tmp_13858_char", ios_base::out);
+  
+  try
+    {
+      fb.sputc('a');
+      fb.sputc('b');
+      fb.pubimbue(locale::classic());
+      fb.sputc('c');
+      fb.pubsync();
+      fb.close();
+    }
+  catch (std::exception&)
+    {
+    }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/2-unbuf.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/2-unbuf.cc
new file mode 100644
index 000000000..792b7970a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/2-unbuf.cc
@@ -0,0 +1,55 @@
+// 2003-06-10  Paolo Carlini  <pcarlini@unitus.it>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_08[] = "filebuf_virtuals-8.txt"; // empty file, need to create
+
+class OverBuf : public std::filebuf
+{
+public:
+  int_type pub_overflow(int_type c = traits_type::eof())
+  { return std::filebuf::overflow(c); }
+};
+
+// According to 27.5.2.4.5 filebuf::overflow() returns not_eof(eof()).
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  typedef OverBuf::traits_type  traits_type;
+
+  OverBuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.open(name_08, ios_base::out | ios_base::trunc);
+  
+  VERIFY( fb.pub_overflow() == traits_type::not_eof(traits_type::eof()) );
+  fb.close();
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/2.cc
new file mode 100644
index 000000000..1cb8e503d
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/2.cc
@@ -0,0 +1,54 @@
+// 2003-06-10  Paolo Carlini  <pcarlini@unitus.it>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_08[] = "filebuf_virtuals-8.txt"; // empty file, need to create
+
+class OverBuf : public std::filebuf
+{
+public:
+  int_type pub_overflow(int_type c = traits_type::eof())
+  { return std::filebuf::overflow(c); }
+};
+
+// According to 27.5.2.4.5 filebuf::overflow() returns not_eof(eof()).
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  typedef OverBuf::traits_type  traits_type;
+
+  OverBuf fb;
+  fb.open(name_08, ios_base::out | ios_base::trunc);
+  
+  VERIFY( fb.pub_overflow() == traits_type::not_eof(traits_type::eof()) );
+  fb.close();
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/3599.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/3599.cc
new file mode 100644
index 000000000..d02872cc0
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/3599.cc
@@ -0,0 +1,58 @@
+// 1999-10-11 bkoz
+
+// Copyright (C) 1999, 2000, 2001, 2002, 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+
+#include <fstream>
+#include <ostream>
+#include <testsuite_hooks.h>
+
+// libstdc++/3599
+class testbuf : public std::filebuf
+{
+public:
+  typedef std::filebuf::traits_type traits_type;
+
+  testbuf() : std::filebuf() { }
+ 
+protected:
+  int_type 
+  overflow(int_type c __attribute__((unused)) = traits_type::eof()) 
+  { return traits_type::not_eof(0); }
+};
+
+void
+test07()
+{
+  bool test __attribute__((unused)) = true;
+  testbuf ob;
+  std::ostream out(&ob); 
+
+  out << "gasp";
+  VERIFY(out.good());
+
+  out << std::endl;
+  VERIFY(out.good());
+}
+
+int main() 
+{
+  test07();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9169.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9169.cc
new file mode 100644
index 000000000..239c79a65
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9169.cc
@@ -0,0 +1,73 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+const char name_04[] = "filebuf_virtuals-4.txt"; // empty file, need to create
+
+class Cvt_to_upper : public std::codecvt<char, char, mbstate_t>
+{
+  bool do_always_noconv() const throw()
+  {
+    return false;
+  }
+};
+
+// libstdc++/9169
+// filebuf output fails if codecvt<>::out returns noconv
+void test10()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale c_loc = locale::classic();
+  locale loc(c_loc, new Cvt_to_upper);
+
+  string str("abcdefghijklmnopqrstuvwxyz");
+  string tmp;
+
+  {
+    ofstream out;
+    out.imbue(loc);
+    out.open(name_04);
+    copy(str.begin(), str.end(), ostreambuf_iterator<char>(out));
+  }
+
+  {
+    ifstream in;
+    in.open(name_04);
+    copy(istreambuf_iterator<char>(in), istreambuf_iterator<char>(),
+	 back_inserter(tmp));
+  }
+
+  VERIFY( tmp.size() == str.size() );
+  VERIFY( tmp == str );
+}
+
+int main() 
+{
+  test10();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9182-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9182-2.cc
new file mode 100644
index 000000000..80d001199
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9182-2.cc
@@ -0,0 +1,80 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+const char name_07[] = "filebuf_virtuals-7.txt"; // empty file, need to create
+
+class errorcvt : public std::codecvt<char, char, mbstate_t>
+{
+protected:
+  std::codecvt_base::result
+  do_out(mbstate_t&, const char* from, const char*,
+	 const char*& from_next, char* to, char*,
+	 char*& to_next) const
+  {
+    from_next = from;
+    to_next = to;
+    return std::codecvt<char, char, mbstate_t>::error;
+  }
+  
+  virtual bool do_always_noconv() const throw()
+  {
+    return false;
+  }
+};
+
+// libstdc++/9182
+// basic_filebuf<>::sync and overflow do not write out any characters
+// if codecvt<>::out returns error
+void test14()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc =  locale::classic();
+  loc = locale(loc, new errorcvt);
+  
+  filebuf fbuf1;
+  fbuf1.pubimbue(loc);
+  fbuf1.pubsetbuf(0, 0);
+  fbuf1.open(name_07, ios_base::out | ios_base::trunc);
+
+  try
+    {
+      fbuf1.sputn("onne", 4);
+      fbuf1.close();
+      VERIFY( false );
+    }
+  catch (std::exception&)
+    {
+    }
+}
+
+int main() 
+{
+  test14();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9988.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9988.cc
new file mode 100644
index 000000000..74dd04bb8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/char/9988.cc
@@ -0,0 +1,70 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_08[] = "filebuf_virtuals-8.txt"; // empty file, need to create
+
+class OverBuf : public std::filebuf
+{
+public:
+  int_type pub_overflow(int_type c = traits_type::eof())
+  { return std::filebuf::overflow(c); }
+};
+
+// libstdc++/9988
+// filebuf::overflow writes EOF to file
+void test15()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  
+  OverBuf fb;
+  fb.open(name_08, ios_base::out | ios_base::trunc);
+  
+  fb.sputc('a');
+  fb.pub_overflow('b');
+  fb.pub_overflow();
+  fb.sputc('c');
+  fb.close();
+
+  filebuf fbin;
+  fbin.open(name_08, ios_base::in);
+  filebuf::int_type c;
+  c = fbin.sbumpc();
+  VERIFY( c == 'a' );
+  c = fbin.sbumpc();
+  VERIFY( c == 'b' );
+  c = fbin.sbumpc();
+  VERIFY( c == 'c' );
+  c = fbin.sbumpc();
+  VERIFY( c == filebuf::traits_type::eof() );
+  fbin.close();
+}
+
+int main() 
+{
+  test15();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-1.cc
new file mode 100644
index 000000000..7faa0501a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-1.cc
@@ -0,0 +1,47 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  wfilebuf fb;
+  locale loc(locale("en_US.UTF-8"));
+  fb.pubimbue(loc);
+  fb.pubsetbuf(0, 0);
+  fb.open("tmp_11305-1", ios_base::out);
+  wfilebuf::int_type n1 = fb.sputc(0x20000000);
+  wfilebuf* f = fb.close();
+  
+  VERIFY( n1 != wfilebuf::traits_type::eof() );
+  VERIFY( f );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-2.cc
new file mode 100644
index 000000000..e4a726a0d
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-2.cc
@@ -0,0 +1,49 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+void test02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  wfilebuf fb;
+  locale loc(locale("en_US.UTF-8"));
+  fb.pubimbue(loc);
+  fb.pubsetbuf(0, 0);
+  fb.open("tmp_11305-2", ios_base::out);
+  wfilebuf::int_type n1 = fb.sputc(0x20000000);
+  wfilebuf::int_type n2 = fb.sputc(0x40000000);
+  wfilebuf* f = fb.close();
+  
+  VERIFY( n1 != wfilebuf::traits_type::eof() );
+  VERIFY( n2 != wfilebuf::traits_type::eof() );
+  VERIFY( f );
+}
+
+int main()
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-3.cc
new file mode 100644
index 000000000..5d49ed0df
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-3.cc
@@ -0,0 +1,46 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+void test03()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  wfilebuf fb;
+  locale loc(locale("en_US.UTF-8"));
+  fb.pubimbue(loc);
+  fb.open("tmp_11305-3", ios_base::out);
+  wfilebuf::int_type n1 = fb.sputc(0x20000000);
+  wfilebuf* f = fb.close();
+	
+  VERIFY( n1 != wfilebuf::traits_type::eof() );
+  VERIFY( f );
+}
+
+int main()
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-4.cc
new file mode 100644
index 000000000..3076a1777
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/11305-4.cc
@@ -0,0 +1,48 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+void test04()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  wfilebuf fb;
+  locale loc(locale("en_US.UTF-8"));
+  fb.pubimbue(loc);
+  fb.open("tmp_11405-4", ios_base::out);
+  wfilebuf::int_type n1 = fb.sputc(0x20000000);
+  wfilebuf::int_type n2 = fb.sputc(0x40000000);
+  wfilebuf* f = fb.close();
+  
+  VERIFY( n1 != wfilebuf::traits_type::eof() );
+  VERIFY( n2 != wfilebuf::traits_type::eof() );
+  VERIFY( f );
+}
+
+int main()
+{
+  test04();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/13858.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/13858.cc
new file mode 100644
index 000000000..dd745267a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/overflow/wchar_t/13858.cc
@@ -0,0 +1,70 @@
+// 2004-02-14  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+protected:
+  virtual std::codecvt_base::result
+  do_out(std::mbstate_t&, const wchar_t* from, const wchar_t*,
+	 const wchar_t*& from_next, char* to, char*,
+	 char*& to_next) const
+  {
+    from_next = from;
+    to_next = to;
+    return std::codecvt_base::error;
+  }
+  
+  virtual bool
+  do_always_noconv() const throw()
+  { return false; }
+};
+
+// libstdc++/13858
+void test01()
+{
+  using namespace std;
+  
+  wfilebuf fb;
+  fb.pubimbue(locale(locale::classic(), new Cvt));
+  fb.open("tmp_13858_wchar_t", ios_base::out);
+  
+  try
+    {
+      fb.sputc(L'a');
+      fb.sputc(L'b');
+      fb.pubimbue(locale::classic());
+      fb.sputc(L'c');
+      fb.pubsync();
+      fb.close();
+    }
+  catch (std::exception&)
+    {
+    }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/pbackfail/char/9761.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/pbackfail/char/9761.cc
new file mode 100644
index 000000000..539460a52
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/pbackfail/char/9761.cc
@@ -0,0 +1,56 @@
+// 2003-06-02 Paolo Carlini <pcarlini@unitus.it>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+// libstdc++/9761
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbuf;
+  filebuf::int_type r1, r2;
+
+  fbuf.open(name_01, ios_base::in);
+  
+  fbuf.sbumpc();
+  fbuf.sbumpc();
+	
+  r1 = fbuf.sputbackc('a');
+  r2 = fbuf.sputbackc('b');
+
+  fbuf.close();
+
+  VERIFY( r1 != filebuf::traits_type::eof() );
+  VERIFY( r2 == filebuf::traits_type::eof() );
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/base_classes.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/base_classes.cc
new file mode 100644
index 000000000..b02fa5be3
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/base_classes.cc
@@ -0,0 +1,43 @@
+// { dg-do compile }
+// 2003-03-26 B enjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.1 - Template class basic_filebuf 
+
+#include <fstream>
+
+void test01()
+{
+  // Check for required base class.
+  typedef std::filebuf test_type;
+  typedef std::streambuf base_type;
+  const test_type& obj = *new test_type();
+  const base_type* base __attribute__((unused)) = &obj;
+}
+
+// more surf!!!
+
+
+
+
+
+
+
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/explicit_instantiation.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/explicit_instantiation.cc
new file mode 100644
index 000000000..dee3b3b35
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/explicit_instantiation.cc
@@ -0,0 +1,49 @@
+// { dg-do compile }
+// 1999-01-17 bkoz test functionality of basic_filebuf for char_type == char
+
+// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.1 - Template class basic_filebuf 
+// NB: This file is for testing basic_filebuf with NO OTHER INCLUDES.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// test05
+// libstdc++/1886
+// should be able to instantiate basic_filebuf for non-standard types.
+namespace std
+{
+  using __gnu_test::pod_char;
+  typedef short type_t;
+  template class basic_filebuf<type_t, char_traits<type_t> >;
+  template class basic_filebuf<pod_char, char_traits<pod_char> >;
+} // test
+
+// more surf!!!
+
+
+
+
+
+
+
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/typedefs.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/typedefs.cc
new file mode 100644
index 000000000..e3539806f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/requirements/typedefs.cc
@@ -0,0 +1,48 @@
+// { dg-do compile }
+// 1999-01-17 bkoz test functionality of basic_filebuf for char_type == char
+
+// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.1 - Template class basic_filebuf 
+// NB: This file is for testing basic_filebuf with NO OTHER INCLUDES.
+
+#include <fstream>
+
+// libstdc++/7216
+void test01()
+{
+  // Check for required typedefs
+  typedef std::filebuf test_type;
+  typedef test_type::char_type char_type;
+  typedef test_type::traits_type traits_type;
+  typedef test_type::int_type int_type;
+  typedef test_type::pos_type pos_type;
+  typedef test_type::off_type off_type;
+}
+
+// more surf!!!
+
+
+
+
+
+
+
+
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-in.cc
new file mode 100644
index 000000000..9e0814ff3
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-in.cc
@@ -0,0 +1,80 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  // int_type sbumpc()
+  // if read_cur not avail returns uflow(), else return *read_cur & increment
+
+  // in 
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( !fb_01.write_position() );
+
+    int_type c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    int_type c3 = fb_01.sbumpc();
+    VERIFY( c3 == '/' );
+
+    c1 = fb_01.sgetc();
+    int_type c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == ' ' );
+    VERIFY( c3 == '9' );
+    VERIFY( c1 == c2 );
+    VERIFY( c2 != c3 );
+
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '9' );
+    VERIFY( c2 == '9' );
+    VERIFY( c3 == '0' );
+
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-io.cc
new file mode 100644
index 000000000..791a6dddb
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-io.cc
@@ -0,0 +1,93 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_03[] = "tmp_sbumpc_1io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  // int_type sbumpc()
+  // if read_cur not avail returns uflow(), else return *read_cur & increment
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; 
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc); 
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+    int_type c5 = fb_03.sbumpc();
+    VERIFY( c5 == traits_type::eof() );
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+  }
+
+  // in | out 2
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::in | ios_base::out);
+    VERIFY( !fb_01.write_position() );
+
+    int_type c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    int_type c3 = fb_01.sbumpc();
+    VERIFY( c3 == '/' );
+
+    c1 = fb_01.sgetc();
+    int_type c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == ' ' );
+    VERIFY( c3 == '9' );
+    VERIFY( c1 == c2 );
+    VERIFY( c2 != c3 );
+
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '9' );
+    VERIFY( c2 == '9' );
+    VERIFY( c3 == '0' );
+
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-out.cc
new file mode 100644
index 000000000..14235217b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/1-out.cc
@@ -0,0 +1,62 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sbumpc_1out.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  // int_type sbumpc()
+  // if read_cur not avail returns uflow(), else return *read_cur & increment
+
+  // out
+  {
+    constraint_filebuf fb_02; 
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+    int_type c2 = fb_02.sbumpc();
+    VERIFY( c2 == traits_type::eof() );
+    int_type c4 = fb_02.sbumpc();
+    VERIFY( c4 == traits_type::eof() );
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-in.cc
new file mode 100644
index 000000000..acb517ebf
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-in.cc
@@ -0,0 +1,80 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  // int_type sbumpc()
+  // if read_cur not avail returns uflow(), else return *read_cur & increment
+
+  // in 
+  {
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( fb_01.unbuffered() );
+
+    int_type c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    int_type c3 = fb_01.sbumpc();
+    VERIFY( c3 == '/' );
+
+    c1 = fb_01.sgetc();
+    int_type c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == ' ' );
+    VERIFY( c3 == '9' );
+    VERIFY( c1 == c2 );
+    VERIFY( c2 != c3 );
+
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '9' );
+    VERIFY( c2 == '9' );
+    VERIFY( c3 == '0' );
+
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-io.cc
new file mode 100644
index 000000000..576dee3ed
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-io.cc
@@ -0,0 +1,92 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_03[] = "tmp_sbumpc_2io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  // int_type sbumpc()
+  // if read_cur not avail returns uflow(), else return *read_cur & increment
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03;
+    fb_03.pubsetbuf(0, 0); 
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc); 
+    VERIFY( fb_03.unbuffered() );
+    int_type c5 = fb_03.sbumpc();
+    VERIFY( c5 == traits_type::eof() );
+    VERIFY( fb_03.unbuffered() );
+  }
+
+  // in | out 2
+  {
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in | ios_base::out);
+    VERIFY( fb_01.unbuffered() );
+
+    int_type c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    int_type c3 = fb_01.sbumpc();
+    VERIFY( c3 == '/' );
+
+    c1 = fb_01.sgetc();
+    int_type c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == ' ' );
+    VERIFY( c3 == '9' );
+    VERIFY( c1 == c2 );
+    VERIFY( c2 != c3 );
+
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sbumpc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '9' );
+    VERIFY( c2 == '9' );
+    VERIFY( c3 == '0' );
+
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-out.cc
new file mode 100644
index 000000000..ccc650e02
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/2-out.cc
@@ -0,0 +1,63 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sbumpc_2out.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  // int_type sbumpc()
+  // if read_cur not avail returns uflow(), else return *read_cur & increment
+
+  // out
+  {
+    constraint_filebuf fb_02; 
+    fb_02.pubsetbuf(0, 0);
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+    int_type c2 = fb_02.sbumpc();
+    VERIFY( c2 == traits_type::eof() );
+    int_type c4 = fb_02.sbumpc();
+    VERIFY( c4 == traits_type::eof() );
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/9825.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/9825.cc
new file mode 100644
index 000000000..50ff2e662
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sbumpc/char/9825.cc
@@ -0,0 +1,56 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_06[] = "filebuf_virtuals-6.txt"; // empty file, need to create
+
+// libstdc++/9825
+// filebuf::sputbackc breaks sbumpc
+void test12()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbuf;
+
+  fbuf.open(name_06, ios_base::in|ios_base::out|ios_base::trunc);
+  fbuf.sputn("crazy bees!", 11);
+  fbuf.pubseekoff(0, ios_base::beg);
+  fbuf.sbumpc();
+  fbuf.sputbackc('x');
+  filebuf::int_type c = fbuf.sbumpc();
+  VERIFY( c == 'x' );
+  c = fbuf.sbumpc();
+  VERIFY( c == 'r' );
+  c = fbuf.sbumpc();
+  VERIFY( c == 'a' );
+  fbuf.close();  
+}
+
+int main() 
+{
+  test12();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/10132-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/10132-2.cc
new file mode 100644
index 000000000..008b56d21
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/10132-2.cc
@@ -0,0 +1,54 @@
+// 2003-04-24 bkoz
+
+// Copyright (C) 2003, 2004, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.1 - Template class basic_filebuf 
+// NB: This file is for testing basic_filebuf with NO OTHER INCLUDES.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/10132, add on
+void test07()
+{
+  bool test __attribute__((unused)) = true;
+  typedef std::basic_filebuf<__gnu_test::pod_ushort> gnu_filebuf;
+  
+  try
+    { 
+      // Need codecvt facet for width argument in seekoff.
+      gnu_filebuf obj;
+      obj.pubseekoff(2, std::ios_base::beg);
+    }
+  catch(std::exception& obj)
+    { 
+      test = false; 
+      VERIFY( test );
+    }
+}
+
+int main() 
+{
+  test07();
+  return 0;
+}
+
+
+
+// more surf!!!
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-1.cc
new file mode 100644
index 000000000..14e0b0a3a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-1.cc
@@ -0,0 +1,83 @@
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.close();
+
+  fb.open(name, ios_base::in);
+  fb.sbumpc();
+  fb.sbumpc();
+  fb.sbumpc();
+
+  // Check that seekoff calls codecvt::length with the correct state.
+  traits_type::pos_type pos = fb.pubseekoff(0, ios_base::cur);
+  VERIFY( pos != traits_type::pos_type(traits_type::off_type(-1)) );
+
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+  fb.sbumpc();
+  fb.sbumpc();
+  c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+  c = fb.sbumpc();
+  VERIFY( c == traits_type::eof() );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-2.cc
new file mode 100644
index 000000000..64ada570c
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-2.cc
@@ -0,0 +1,86 @@
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.close();
+
+  fb.open(name, ios_base::in);
+  fb.sbumpc();
+  fb.sbumpc();
+  fb.sbumpc();
+
+  // Check that seekoff resets the state when seeking to beginning.
+  traits_type::pos_type pos = fb.pubseekoff(0, ios_base::beg);
+  VERIFY( pos != traits_type::pos_type(traits_type::off_type(-1)) );
+
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>(0xff)) );
+  fb.sbumpc();
+  fb.sbumpc();
+  fb.sbumpc();
+  fb.sbumpc();
+  fb.sbumpc();
+  c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+  c = fb.sbumpc();
+  VERIFY( c == traits_type::eof() );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-3.cc
new file mode 100644
index 000000000..79cda63fe
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-3.cc
@@ -0,0 +1,81 @@
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out | ios_base::trunc);
+  fb.sputc(pod_uchar::from<char>('b'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>(0xfc));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+
+  fb.close();
+  fb.open(name, ios_base::in);
+
+  fb.sbumpc();
+  fb.sbumpc();
+
+  // Check that seekoff returns the correct state
+  traits_type::pos_type pos = fb.pubseekoff(0, ios_base::cur);
+
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+  fb.sbumpc();
+
+  fb.pubseekpos(pos);
+
+  c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-4.cc
new file mode 100644
index 000000000..3bf4353d7
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/12790-4.cc
@@ -0,0 +1,72 @@
+// Copyright (C) 2003, 2005, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+  fb.sputc(pod_uchar::from<char>('b'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+
+  // Check that seekoff sets the current state during output
+  fb.pubseekoff(0, ios_base::cur);
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+
+  fb.pubseekoff(0, ios_base::beg);
+  fb.sbumpc();
+  fb.sbumpc();
+
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/45628-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/45628-2.cc
new file mode 100644
index 000000000..6e40a89aa
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/45628-2.cc
@@ -0,0 +1,103 @@
+// Copyright (C) 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+const char name_01[] = "tmp_seekoff_45628.tst";
+
+unsigned underflows, overflows;
+
+class my_filebuf
+: public std::basic_filebuf<__gnu_test::pod_uchar>
+{
+  virtual int_type
+  underflow()
+  {
+    ++underflows;
+    return std::basic_filebuf<__gnu_test::pod_uchar>::underflow();
+  }
+  virtual int_type
+  overflow(int_type c)
+  {
+    ++overflows;
+    return std::basic_filebuf<__gnu_test::pod_uchar>::overflow(c);
+  }
+};
+
+// libstdc++/45628
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  using __gnu_test::pod_uchar;
+  std::locale loc(std::locale::classic(),
+	     new std::codecvt<my_filebuf::traits_type::char_type, char,
+	     my_filebuf::traits_type::state_type>);
+
+  my_filebuf::pos_type opos[3], ipos[3];
+  my_filebuf q;
+  q.pubimbue(loc);
+   
+  q.open(name_01, std::ios_base::in | std::ios_base::out 
+	 | std::ios_base::trunc); 
+
+  q.sputc(pod_uchar::from<char>('a'));
+  opos[0] = q.pubseekoff(0, std::ios_base::cur);
+  q.sputc(pod_uchar::from<char>('b'));
+  opos[1] = q.pubseekoff(0, std::ios_base::cur);
+  q.sputc(pod_uchar::from<char>('c'));
+  opos[2] = q.pubseekoff(0, std::ios_base::cur);
+
+  VERIFY( overflows <= 9 ); // pubseekoff calls overflow twice if converting.
+  // NB: checking opos==ipos is not very rigorous as long as it flushes, since
+  // all positions will be at initial state.
+  q.pubseekoff(0, std::ios_base::beg);
+
+  q.sbumpc();
+  VERIFY( underflows == 1 );
+
+  ipos[0] = q.pubseekoff(0, std::ios_base::cur);
+  VERIFY( ipos[0] == opos[0] );
+  q.sbumpc();
+  ipos[1] = q.pubseekoff(0, std::ios_base::cur);
+  VERIFY( ipos[1] == opos[1] );
+  q.sbumpc();
+  ipos[2] = q.pubseekoff(0, std::ios_base::cur);
+  VERIFY( ipos[2] == opos[2] );
+
+  VERIFY( underflows == 1 ); // pubseekoff never flushes get area
+  
+  // Bonus test: check automatic mode switches.
+  q.sputc(pod_uchar::from<char>('d'));
+  
+  q.pubseekpos( ipos[1] );
+  q.sputc(pod_uchar::from<char>('e'));
+  
+  VERIFY( my_filebuf::traits_type::eq(
+			my_filebuf::traits_type::to_char_type(q.sgetc()),
+			pod_uchar::from<char>('d')) );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-in.cc
new file mode 100644
index 000000000..248874617
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-in.cc
@@ -0,0 +1,124 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekoff.txt";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekoff
+  // pubseekoff(off_type off, ios_base::seekdir way, ios_base::openmode which)
+  // alters the stream position to off
+
+  // in
+  {
+    constraint_filebuf fb;
+    fb.open(name_01, ios_base::in);
+    VERIFY( !fb.write_position() );
+
+    //beg
+    strmsz_1 = fb.in_avail(); 
+    pt_1 = fb.pubseekoff(2, ios_base::beg);
+    fb.in_avail(); 
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '9' );
+    fb.pubseekoff(3, ios_base::beg);
+    c2 = fb.sputc('\n');  //current in pointer +1
+    fb.pubseekoff(4, ios_base::beg);
+    c3 = fb.sgetc();
+    VERIFY( c2 == traits_type::eof() ); 
+    VERIFY( c3 == '9' );
+    fb.pubsync(); 
+    c1 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //cur
+    pt_2 = fb.pubseekoff(2, ios_base::cur);
+    off_2 = off_type(pt_2);
+    VERIFY( (off_2 == (off_1 + 2 + 1 + 1)) );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '1' );
+    fb.pubseekoff(0, ios_base::cur);
+    c2 = fb.sputc('x');  //test current out pointer
+    c3 = fb.sputc('\n');
+    VERIFY( c2 == traits_type::eof() );
+    VERIFY( c3 == traits_type::eof() );
+    fb.pubseekoff(0, ios_base::cur);
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //end
+    pt_2 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_2);
+    VERIFY( off_1 > off_2 ); //weak, but don't know exactly where it ends
+    c3 = fb.sputc('\n');
+    strmsz_1 = fb.sputn("because because because. . .", 28);  
+    VERIFY( strmsz_1 == 0 );
+    fb.pubseekoff(-1, ios_base::end);
+    fb.sgetc();
+    c1 = fb.sungetc();
+    // Defect?  retval of sungetc is not necessarily the character ungotten.
+    // So re-get it.
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+    VERIFY( !fb.write_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-io.cc
new file mode 100644
index 000000000..4dc6d8648
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-io.cc
@@ -0,0 +1,124 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+// { dg-require-binary-io "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekoff-1io.tst";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekoff
+  // pubseekoff(off_type off, ios_base::seekdir way, ios_base::openmode which)
+  // alters the stream position to off
+
+  // in | out
+  {
+    constraint_filebuf fb;
+    fb.open(name_01, ios_base::out | ios_base::in);
+    VERIFY( !fb.write_position() );
+    VERIFY( !fb.read_position() );
+
+    //beg
+    strmsz_1 = fb.in_avail(); 
+    pt_1 = fb.pubseekoff(2, ios_base::beg);
+    fb.in_avail(); 
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '9' );
+    fb.pubseekoff(3, ios_base::beg);
+    c2 = fb.sputc('\n');  //current in pointer +1
+    fb.pubseekoff(4, ios_base::beg);
+    c3 = fb.sgetc();
+    VERIFY( c2 != c3 ); 
+    VERIFY( c3 == '9' );
+    fb.pubsync(); 
+    c1 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //cur
+    pt_2 = fb.pubseekoff(2, ios_base::cur);
+    off_2 = off_type(pt_2);
+    VERIFY( (off_2 == (off_1 + 2 + 1 + 1)) );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '1' );
+    fb.pubseekoff(0, ios_base::cur);
+    c2 = fb.sputc('x');  //test current out pointer
+    c3 = fb.sputc('\n');
+    fb.pubseekoff(0, ios_base::cur);
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //end
+    pt_2 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_2);
+    VERIFY( off_1 > off_2 ); //weak, but don't know exactly where it ends
+    c3 = fb.sputc('\n');
+    strmsz_1 = fb.sputn("because because because. . .", 28);  
+    VERIFY( strmsz_1 == 28 );
+    fb.pubseekoff(-1, ios_base::end);
+    fb.sgetc();
+    c1 = fb.sungetc();
+    // Defect?  retval of sungetc is not necessarily the character ungotten.
+    // So re-get it.
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+    VERIFY( !fb.write_position() );
+    VERIFY( fb.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-out.cc
new file mode 100644
index 000000000..8d7ab1dfc
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/1-out.cc
@@ -0,0 +1,124 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekoff-1out.tst";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekoff
+  // pubseekoff(off_type off, ios_base::seekdir way, ios_base::openmode which)
+  // alters the stream position to off
+
+  // out
+  {
+    constraint_filebuf fb;
+    fb.open(name_01, ios_base::out);
+    VERIFY( !fb.write_position() );
+    VERIFY( !fb.read_position() );
+
+    //beg
+    strmsz_1 = fb.in_avail(); 
+    pt_1 = fb.pubseekoff(2, ios_base::beg);
+    fb.in_avail(); 
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == traits_type::eof() );
+    fb.pubseekoff(3, ios_base::beg);
+    c2 = fb.sputc('\n');  //current in pointer +1
+    fb.pubseekoff(4, ios_base::beg);
+    c3 = fb.sgetc();
+    VERIFY( c2 != c3 ); 
+    VERIFY( c3 == traits_type::eof() );
+    fb.pubsync(); 
+    c1 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //cur
+    pt_2 = fb.pubseekoff(2, ios_base::cur);
+    off_2 = off_type(pt_2);
+    VERIFY( (off_2 == (off_1 + 2 + 1 + 1)) );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == traits_type::eof() );
+    fb.pubseekoff(0, ios_base::cur);
+    c2 = fb.sputc('x');  //test current out pointer
+    c3 = fb.sputc('\n');
+    fb.pubseekoff(0, ios_base::cur);
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //end
+    pt_2 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_2);
+    VERIFY( off_1 > off_2 ); //weak, but don't know exactly where it ends
+    c3 = fb.sputc('\n');
+    strmsz_1 = fb.sputn("because because because. . .", 28);  
+    VERIFY( strmsz_1 == 28 );
+    fb.pubseekoff(-1, ios_base::end);
+    fb.sgetc();
+    c1 = fb.sungetc();
+    // Defect?  retval of sungetc is not necessarily the character ungotten.
+    // So re-get it.
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+    VERIFY( !fb.write_position() );
+    VERIFY( !fb.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/11543.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/11543.cc
new file mode 100644
index 000000000..2f6cf2988
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/11543.cc
@@ -0,0 +1,153 @@
+// Copyright (C) 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+struct MyState
+{
+};
+
+struct MyCharTraits : std::char_traits<char>
+{
+  typedef std::fpos<MyState> pos_type;
+  typedef MyState state_type;
+};
+
+namespace std
+{
+  template <>
+    class codecvt<char, char, MyState> :
+      public locale::facet, public codecvt_base
+    {
+    public:
+      typedef char intern_type;
+      typedef char extern_type;
+      typedef MyState state_type;
+    
+      explicit codecvt(size_t refs = 0)
+      : locale::facet(refs) { }
+    
+      result out(state_type& state, const intern_type* from,
+		 const intern_type* from_end,  const intern_type*& from_next,
+		 extern_type* to, extern_type* to_limit,
+		 extern_type*& to_next) const
+      { return do_out(state, from, from_end, from_next,
+		      to, to_limit, to_next); }
+
+      result unshift(state_type& state, extern_type* to, extern_type* to_limit,
+		     extern_type*& to_next) const
+      { return do_unshift(state, to, to_limit, to_next); }
+
+      result in(state_type& state, const extern_type* from,
+		const extern_type* from_end, const extern_type*& from_next,
+		intern_type* to, intern_type* to_limit,
+		intern_type*& to_next) const
+      { return do_in(state, from, from_end, from_next,
+		     to, to_limit, to_next); }
+
+      int encoding() const throw()
+      { return do_encoding(); }
+      
+      bool always_noconv() const throw()
+      { return do_always_noconv(); }
+
+      int length(state_type& state, const extern_type* from,
+		 const extern_type* end, size_t max) const
+      { return do_length(state, from, end, max); }
+
+      int max_length() const throw()
+      { return do_max_length(); }
+    
+      static locale::id id;
+    
+    protected:
+      virtual ~codecvt();
+
+      virtual result do_out(state_type&, const intern_type* from,
+			    const intern_type*, const intern_type*& from_next,
+			    extern_type* to, extern_type*,
+			    extern_type*& to_next) const
+      {
+	from_next = from;
+	to_next = to;
+	return noconv;
+      }
+
+      virtual result do_in(state_type&, const extern_type* from,
+			   const extern_type*, const extern_type*& from_next,
+			   intern_type* to, intern_type*,
+			   intern_type*& to_next) const
+      {
+	from_next = from;
+	to_next = to;
+	return noconv;
+      }
+
+      virtual result do_unshift(state_type&, extern_type*, extern_type*,
+				extern_type*&) const
+      { return noconv; }
+
+      virtual int do_encoding() const throw()
+      { return 1; }
+
+      virtual bool do_always_noconv() const throw()
+      { return true; }
+
+      virtual int do_length(state_type&, const extern_type* from,
+			    const extern_type* end, size_t max) const
+      {
+	size_t len = end - from;
+	return std::min(max, len);
+      }
+
+      virtual int do_max_length() const throw()
+      { return 1; }
+    };
+  
+  locale::id codecvt<char, char, MyState>::id;
+
+  codecvt<char, char, MyState>::~codecvt()
+  { }
+}
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  std::locale loc(std::locale::classic(),
+		  new std::codecvt<char, char, MyState>);
+  std::basic_filebuf<char, MyCharTraits> fb;
+  fb.pubimbue(loc);
+  fb.open("tmp_11543", std::ios_base::out);
+  VERIFY( fb.is_open() );
+  MyCharTraits::pos_type pos = fb.pubseekoff(0, std::ios_base::beg);
+  VERIFY( pos != MyCharTraits::pos_type(MyCharTraits::off_type(-1)) );
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12232.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12232.cc
new file mode 100644
index 000000000..a60293274
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12232.cc
@@ -0,0 +1,71 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name[] = "tmp_12232";
+
+// libstdc++/12232
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbout;
+  fbout.open(name, ios_base::out);
+  fbout.sputn("abc", 3);
+  
+  streampos p1 = fbout.pubseekoff(0, ios_base::cur, ios_base::in);
+  VERIFY( p1 != streampos(-1) );
+  fbout.sputn("de", 2);
+  
+  streampos p2 = fbout.pubseekpos(p1, ios_base::openmode());
+  VERIFY( p2 != streampos(-1) );
+  fbout.sputn("34", 2);
+  
+  streampos p3 = fbout.pubseekoff(0, ios_base::beg, ios_base::ate);
+  VERIFY( p3 != streampos(-1) );
+  fbout.sputn("012", 3);
+  
+  fbout.close();
+  
+  filebuf fbin;
+  fbin.open(name, ios_base::in);
+  
+  streampos p4 = fbin.pubseekoff(0, ios_base::beg, ios_base::ate);
+  VERIFY( p4 != streampos(-1) );
+  VERIFY( fbin.sgetc() == '0' );
+  
+  streampos p5 = fbin.pubseekoff(-1, ios_base::end, ios_base::out);
+  VERIFY( p5 != streampos(-1) );
+  VERIFY( fbin.sbumpc() == '4' );
+  
+  streampos p6 = fbin.pubseekpos(p4, ios_base::binary);
+  VERIFY( p6 != streampos(-1) );
+  VERIFY( fbin.sbumpc() == '0' );
+  
+  fbin.close();
+}
+
+int main()
+{
+  void test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-1.cc
new file mode 100644
index 000000000..d2860cbf5
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-1.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-2.cc
new file mode 100644
index 000000000..f0f1b9938
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-2.cc
@@ -0,0 +1,81 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-3.cc
new file mode 100644
index 000000000..026d75029
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-3.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift(),
+// but only if writing
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( !cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-4.cc
new file mode 100644
index 000000000..60813c899
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/12790-4.cc
@@ -0,0 +1,81 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc('a');
+  fb.pubsync(); // Does not call unshift()
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-in.cc
new file mode 100644
index 000000000..3a8809da2
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-in.cc
@@ -0,0 +1,125 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekoff.txt";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekoff
+  // pubseekoff(off_type off, ios_base::seekdir way, ios_base::openmode which)
+  // alters the stream position to off
+
+  // in
+  {
+    constraint_filebuf fb;
+    fb.pubsetbuf(0, 0);
+    fb.open(name_01, ios_base::in);
+    VERIFY( fb.unbuffered() );
+
+    //beg
+    strmsz_1 = fb.in_avail(); 
+    pt_1 = fb.pubseekoff(2, ios_base::beg);
+    fb.in_avail(); 
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '9' );
+    fb.pubseekoff(3, ios_base::beg);
+    c2 = fb.sputc('\n');  //current in pointer +1
+    fb.pubseekoff(4, ios_base::beg);
+    c3 = fb.sgetc();
+    VERIFY( c2 == traits_type::eof() ); 
+    VERIFY( c3 == '9' );
+    fb.pubsync(); 
+    c1 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //cur
+    pt_2 = fb.pubseekoff(2, ios_base::cur);
+    off_2 = off_type(pt_2);
+    VERIFY( (off_2 == (off_1 + 2 + 1 + 1)) );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '1' );
+    fb.pubseekoff(0, ios_base::cur);
+    c2 = fb.sputc('x');  //test current out pointer
+    c3 = fb.sputc('\n');
+    VERIFY( c2 == traits_type::eof() );
+    VERIFY( c3 == traits_type::eof() );
+    fb.pubseekoff(0, ios_base::cur);
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //end
+    pt_2 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_2);
+    VERIFY( off_1 > off_2 ); //weak, but don't know exactly where it ends
+    c3 = fb.sputc('\n');
+    strmsz_1 = fb.sputn("because because because. . .", 28);  
+    VERIFY( strmsz_1 == 0 );
+    fb.pubseekoff(-1, ios_base::end);
+    fb.sgetc();
+    c1 = fb.sungetc();
+    // Defect?  retval of sungetc is not necessarily the character ungotten.
+    // So re-get it.
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+    VERIFY( fb.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-io.cc
new file mode 100644
index 000000000..89fab2aed
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-io.cc
@@ -0,0 +1,123 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+// { dg-require-binary-io "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekoff-2io.tst";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekoff
+  // pubseekoff(off_type off, ios_base::seekdir way, ios_base::openmode which)
+  // alters the stream position to off
+
+  // in | out
+  {
+    constraint_filebuf fb;
+    fb.pubsetbuf(0, 0);
+    fb.open(name_01, ios_base::out | ios_base::in);
+    VERIFY( fb.unbuffered() );
+
+    //beg
+    strmsz_1 = fb.in_avail(); 
+    pt_1 = fb.pubseekoff(2, ios_base::beg);
+    fb.in_avail(); 
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '9' );
+    fb.pubseekoff(3, ios_base::beg);
+    c2 = fb.sputc('\n');  //current in pointer +1
+    fb.pubseekoff(4, ios_base::beg);
+    c3 = fb.sgetc();
+    VERIFY( c2 != c3 ); 
+    VERIFY( c3 == '9' );
+    fb.pubsync(); 
+    c1 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //cur
+    pt_2 = fb.pubseekoff(2, ios_base::cur);
+    off_2 = off_type(pt_2);
+    VERIFY( (off_2 == (off_1 + 2 + 1 + 1)) );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == '1' );
+    fb.pubseekoff(0, ios_base::cur);
+    c2 = fb.sputc('x');  //test current out pointer
+    c3 = fb.sputc('\n');
+    fb.pubseekoff(0, ios_base::cur);
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //end
+    pt_2 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_2);
+    VERIFY( off_1 > off_2 ); //weak, but don't know exactly where it ends
+    c3 = fb.sputc('\n');
+    strmsz_1 = fb.sputn("because because because. . .", 28);  
+    VERIFY( strmsz_1 == 28 );
+    fb.pubseekoff(-1, ios_base::end);
+    fb.sgetc();
+    c1 = fb.sungetc();
+    // Defect?  retval of sungetc is not necessarily the character ungotten.
+    // So re-get it.
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+    VERIFY( fb.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-out.cc
new file mode 100644
index 000000000..b1ad66e89
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/2-out.cc
@@ -0,0 +1,123 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekoff-2out.tst";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekoff
+  // pubseekoff(off_type off, ios_base::seekdir way, ios_base::openmode which)
+  // alters the stream position to off
+
+  // out
+  {
+    constraint_filebuf fb;
+    fb.pubsetbuf(0, 0);
+    fb.open(name_01, ios_base::out);
+    VERIFY( fb.unbuffered() );
+
+    //beg
+    strmsz_1 = fb.in_avail(); 
+    pt_1 = fb.pubseekoff(2, ios_base::beg);
+    fb.in_avail(); 
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == traits_type::eof() );
+    fb.pubseekoff(3, ios_base::beg);
+    c2 = fb.sputc('\n');  //current in pointer +1
+    fb.pubseekoff(4, ios_base::beg);
+    c3 = fb.sgetc();
+    VERIFY( c2 != c3 ); 
+    VERIFY( c3 == traits_type::eof() );
+    fb.pubsync(); 
+    c1 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //cur
+    pt_2 = fb.pubseekoff(2, ios_base::cur);
+    off_2 = off_type(pt_2);
+    VERIFY( (off_2 == (off_1 + 2 + 1 + 1)) );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == traits_type::eof() );
+    fb.pubseekoff(0, ios_base::cur);
+    c2 = fb.sputc('x');  //test current out pointer
+    c3 = fb.sputc('\n');
+    fb.pubseekoff(0, ios_base::cur);
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+
+    //end
+    pt_2 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_2);
+    VERIFY( off_1 > off_2 ); //weak, but don't know exactly where it ends
+    c3 = fb.sputc('\n');
+    strmsz_1 = fb.sputn("because because because. . .", 28);  
+    VERIFY( strmsz_1 == 28 );
+    fb.pubseekoff(-1, ios_base::end);
+    fb.sgetc();
+    c1 = fb.sungetc();
+    // Defect?  retval of sungetc is not necessarily the character ungotten.
+    // So re-get it.
+    c1 = fb.sgetc();
+    fb.pubsync(); 
+    c3 = fb.sgetc();
+    VERIFY( c1 == c3 );
+    VERIFY( fb.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/26777.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/26777.cc
new file mode 100644
index 000000000..d98234bab
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/26777.cc
@@ -0,0 +1,90 @@
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// 2006-03-22  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2006, 2007, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// No asserts, avoid leaking the semaphores if a VERIFY fails.
+#undef _GLIBCXX_ASSERT
+
+#include <testsuite_hooks.h>
+#include <fstream>
+#include <sstream>
+#include <cstdlib>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+// libstdc++/26777
+bool test01()
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  bool test __attribute__((unused)) = true;
+
+  const char* name = "tmp_fifo6";
+
+  signal(SIGPIPE, SIG_IGN);
+
+  unlink(name);  
+  mkfifo(name, S_IRWXU);
+  semaphore s1, s2;
+
+  int child = fork();
+  VERIFY( child != -1 );
+
+  if (child == 0)
+    {
+      filebuf fbout;
+      fbout.open(name, ios_base::in | ios_base::out);
+      VERIFY( fbout.is_open() );
+      fbout.sputn("Whatever", 8);
+      fbout.pubsync();
+      s1.signal();
+      s2.wait();
+      fbout.close();
+      s1.signal();
+      exit(0);
+    }
+
+  filebuf fbin;
+  fbin.open(name, ios::in);
+  s1.wait();
+
+  fbin.sgetc();
+  fbin.pubseekoff(0, ios::cur, ios::in);
+  s2.signal();
+  s1.wait();
+
+  ostringstream oss;
+  oss << &fbin;
+  fbin.close();
+
+  VERIFY( oss.str() == "Whatever" );
+
+  return test;
+}
+
+int main()
+{
+  return !test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-in.cc
new file mode 100644
index 000000000..a0c4d5a86
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-in.cc
@@ -0,0 +1,63 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.7.1.3 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test02(std::filebuf& in, bool pass)
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  typedef streambuf::pos_type pos_type;
+  typedef streambuf::off_type off_type;
+  pos_type bad = pos_type(off_type(-1));
+  pos_type p = 0;
+
+  // seekoff
+  p = in.pubseekoff(0, ios_base::beg, ios_base::in);
+  VERIFY( pass == (p != bad) );
+
+  p = in.pubseekoff(0, ios_base::beg, ios_base::out);
+  VERIFY( pass == (p != bad) );  // See libstdc++/12232
+
+  p = in.pubseekoff(0, ios_base::beg); 
+  VERIFY( pass == (p != bad) );
+}
+
+const char name_01[] = "filebuf_virtuals-1.tst"; // file with data in it
+const char name_03[] = "filebuf_members-1.tst"; // empty file
+
+int main() 
+{
+  using namespace std;
+
+  filebuf in1;
+  in1.open(name_01, ios_base::in);
+  filebuf in2;
+  filebuf in3;
+  in3.open(name_03, ios_base::in);
+  test02(in1, true);
+  test02(in2, false);
+  test02(in3, true);
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-io.cc
new file mode 100644
index 000000000..803a81f27
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-io.cc
@@ -0,0 +1,66 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.7.1.3 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test02(std::filebuf& in, bool pass)
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  typedef streambuf::pos_type pos_type;
+  typedef streambuf::off_type off_type;
+  pos_type bad = pos_type(off_type(-1));
+  pos_type p = 0;
+
+  // seekoff
+  p = in.pubseekoff(0, ios_base::beg, ios_base::in);
+  if (pass)
+    VERIFY( p != bad );
+
+  p = in.pubseekoff(0, ios_base::beg, ios_base::out); 
+  if (pass)
+    VERIFY( p != bad );
+
+  p = in.pubseekoff(0, ios_base::beg); 
+  if (pass)
+    VERIFY( p != bad );
+}
+
+const char name_01[] = "filebuf_virtuals-1.tst"; // file with data in it
+const char name_03[] = "filebuf_members-1.tst"; // empty file
+
+int main() 
+{
+  using namespace std;
+
+  filebuf in1;
+  in1.open(name_01, ios_base::in | ios_base::out);
+  filebuf in2;
+  filebuf in3;
+  in3.open(name_03, ios_base::in | ios_base::out);
+  test02(in1, true);
+  test02(in2, false);
+  test02(in3, true);
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-out.cc
new file mode 100644
index 000000000..08eac2933
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/3-out.cc
@@ -0,0 +1,63 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.7.1.3 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test02(std::filebuf& in, bool pass)
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  typedef streambuf::pos_type pos_type;
+  typedef streambuf::off_type off_type;
+  pos_type bad = pos_type(off_type(-1));
+  pos_type p = 0;
+
+  // seekoff
+  p = in.pubseekoff(0, ios_base::beg, ios_base::in);
+  VERIFY( pass == (p != bad) );  // See libstdc++/12232
+
+  p = in.pubseekoff(0, ios_base::beg, ios_base::out); 
+  VERIFY( pass == (p != bad) );
+
+  p = in.pubseekoff(0, ios_base::beg); 
+  VERIFY( pass == (p != bad) );
+}
+
+const char name_01[] = "filebuf_virtuals-1.tst"; // file with data in it
+const char name_03[] = "filebuf_members-1.tst"; // empty file
+
+int main() 
+{
+  using namespace std;
+
+  filebuf out1;
+  out1.open(name_01, ios_base::out);
+  filebuf out2;
+  filebuf out3;
+  out3.open(name_03, ios_base::out);
+  test02(out1, true);
+  test02(out2, false);
+  test02(out3, true);
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/4.cc
new file mode 100644
index 000000000..fe21b3a88
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/4.cc
@@ -0,0 +1,93 @@
+// { dg-require-fileio "" }
+
+// Copyright (C) 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  typedef filebuf::pos_type pos_type;
+  const char name[] = "tmp_seekoff-4.tst";
+
+  const size_t size = 12;
+  char buf[size];
+  streamsize n;
+
+  filebuf fb;
+  fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+
+  n = fb.sputn("abcd", 4);
+  VERIFY( n == 4 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 3);
+  VERIFY( n == 3 );
+  VERIFY( !memcmp(buf, "abc", 3) );
+
+  // Check read => write without pubseekoff(0, ios_base::cur)
+
+  n = fb.sputn("ef", 2);
+  VERIFY( n == 2 );
+
+  fb.pubseekoff(0, ios_base::beg);
+
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 5 );
+  VERIFY( !memcmp(buf, "abcef", 5) );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sputn("gh", 2);
+  VERIFY( n == 2 );
+  
+  // Check write => read without pubseekoff(0, ios_base::cur)
+
+  n = fb.sgetn( buf, 3 );
+  VERIFY( !memcmp(buf, "cef", 3) );
+
+  n = fb.sputn("ijkl", 4);
+  VERIFY( n == 4 );
+  
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 2);
+  VERIFY( n == 2 );
+  VERIFY( !memcmp(buf, "gh", 2) );
+
+  fb.pubseekoff(0, ios_base::end);
+  n = fb.sputn("mno", 3);
+  VERIFY( n == 3 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 12 );
+  VERIFY( !memcmp(buf, "ghcefijklmno", 12) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/45628-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/45628-1.cc
new file mode 100644
index 000000000..a80a33876
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/45628-1.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "tmp_seekoff_45628.tst";
+
+unsigned underflows, overflows;
+
+class my_filebuf
+: public std::filebuf
+{
+  virtual int_type
+  underflow()
+  {
+    ++underflows;
+    return std::filebuf::underflow();
+  }
+  virtual int_type
+  overflow(int_type c)
+  {
+    ++overflows;
+    return std::filebuf::overflow(c);
+  }
+};
+
+// libstdc++/45628
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  my_filebuf q;
+  q.open(name_01, std::ios_base::in | std::ios_base::out 
+	 | std::ios_base::trunc); 
+
+  q.sputc('a');
+  q.pubseekoff(0, std::ios_base::cur);
+  q.sputc('b');
+  q.pubseekoff(0, std::ios_base::cur);
+  q.sputc('c');
+  q.pubseekoff(0, std::ios_base::cur);
+
+  VERIFY( overflows <= 1 ); // only initial sputc allowed to overflow
+  q.pubseekoff(0, std::ios_base::beg);
+
+  q.sbumpc();
+  VERIFY( underflows == 1 );
+
+  q.pubseekoff(0, std::ios_base::cur);
+  q.sbumpc();
+  q.pubseekoff(0, std::ios_base::cur);
+  q.sbumpc();
+  q.pubseekoff(0, std::ios_base::cur);
+
+  VERIFY( underflows == 1 );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc
new file mode 100644
index 000000000..c6f13dcd0
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc
@@ -0,0 +1,137 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-09-08  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Check that basic_filebuf::seekoff handles UTF-8 when open for input.
+void test01()
+{
+  using namespace std;
+  typedef wfilebuf::pos_type pos_type;
+  typedef wfilebuf::int_type int_type;
+
+  bool test __attribute__((unused)) = true;
+  const char name[] = "tmp_seekoff-1.tst";
+  const int_type eof = wfilebuf::traits_type::eof();
+
+  const char cstr[] =
+    "\x1\x2\x3\x4\x5\x6\x7\x8\x9\xa\xb\xc\xd\xe\xf\x10\x11\x12\x13"
+    "\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20!\"#$%&"
+    "'()*+,-./0123456789:;<=>?@}~\x7f\xc2\x80\xc2\x81\xc2\x82\xc2"
+    "\x83\xc2\x84\xc2\x85\xc2\x86\xc2\x87\xc2\x88\xc2\x89\xc2\x8a"
+    "\xc2\x8b\xc2\x8c\xc2\x8d\xc2\x8e\xc2\x8f\xc2\x90\xc2\x91\xc2"
+    "\x92\xc2\x93\xc2\x94\xc2\x95\xc2\x96\xc2\x97\xc2\x98\xc2\x99"
+    "\xc2\x9a\xc2\x9b\xc2\x9c\xc3\xba\xc3\xbb\xc3\xbc\xc3\xbd\xc3"
+    "\xbe\xc3\xbf\xc4\x80\xc4\x81\xc4\x82\xc4\x83\xc4\x84\xc4\x85"
+    "\xc4\x86\xc4\x87\xc4\x88\xc4\x89\xc4\x8a\xc4\x8b\xc4\x8c\xc4"
+    "\x8d\xc4\x8e\xc4\x8f\xc4\x90\xc4\x91\xc4\x92\xc4\x93\xc4\x94"
+    "\xc4\x95\xc4\x96\xc4\x97\xc4\x98\xc4\x99\xdf\xb8\xdf\xb9\xdf"
+    "\xba\xdf\xbb\xdf\xbc\xdf\xbd\xdf\xbe\xdf\xbf\xe0\xa0\x80\xe0"
+    "\xa0\x81\xe0\xa0\x82\xe0\xa0\x83\xe0\xa0\x84\xe0\xa0\x85\xe0"
+    "\xa0\x86\xe0\xa0\x87\xe0\xa0\x88\xe0\xa0\x89\xe0\xa0\x8a\xe0"
+    "\xa0\x8b\xe0\xa0\x8c\xe0\xa0\x8d\xe0\xa0\x8e\xe0\xa0\x8f\xe0"
+    "\xa0\x90\xe0\xa0\x91\xe0\xa0\x92\xe0\xa0\x93\xe0\xa0\x94\xe0"
+    "\xa0\x95\xe0\xa0\x96\xe0\xa0\x97\x1\x2\x4\x8\x10\x20@\xc2\x80"
+    "\xc4\x80\xc8\x80\xd0\x80\xe0\xa0\x80\xe1\x80\x80\xe2\x80\x80"
+    "\xe4\x80\x80\xe8\x80\x80\xf0\x90\x80\x80\xf0\xa0\x80\x80\xf1"
+    "\x80\x80\x80\xf2\x80\x80\x80\xf4\x80\x80\x80\xf8\x88\x80\x80"
+    "\x80\xf8\x90\x80\x80\x80\xf8\xa0\x80\x80\x80\xf9\x80\x80\x80"
+    "\x80\xfa\x80\x80\x80\x80\xfc\x84\x80\x80\x80\x80\xfc\x88\x80"
+    "\x80\x80\x80\xfc\x90\x80\x80\x80\x80\xfc\xa0\x80\x80\x80\x80"
+    "\xfd\x80\x80\x80\x80\x80";
+
+  const wchar_t wstr[] = {
+    0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc,
+    0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, L'!',
+    L'"', L'#', L'$', L'%', L'&', L'\'', L'(', L')', L'*', L'+',
+    L',', L'-', L'.', L'/', L'0', L'1', L'2', L'3', L'4', L'5',
+    L'6', L'7', L'8', L'9', L':', L';', L'<', L'=', L'>', L'?',
+    L'@', L'}', L'~', 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
+    0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+    0x9a, 0x9b, 0x9c, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 0x100,
+    0x101, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107, 0x108, 0x109,
+    0x10a, 0x10b, 0x10c, 0x10d, 0x10e, 0x10f, 0x110, 0x111, 0x112,
+    0x113, 0x114, 0x115, 0x116, 0x117, 0x118, 0x119, 0x7f8, 0x7f9,
+    0x7fa, 0x7fb, 0x7fc, 0x7fd, 0x7fe, 0x7ff, 0x800, 0x801, 0x802,
+    0x803, 0x804, 0x805, 0x806, 0x807, 0x808, 0x809, 0x80a, 0x80b,
+    0x80c, 0x80d, 0x80e, 0x80f, 0x810, 0x811, 0x812, 0x813, 0x814,
+    0x815, 0x816, 0x817, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, L'@',
+    0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000,
+    0x10000, 0x20000, 0x40000, 0x80000, 0x100000, 0x200000, 0x400000,
+    0x800000, 0x1000000, 0x2000000, 0x4000000, 0x8000000, 0x10000000,
+    0x20000000, 0x40000000, 0x0
+  };
+
+  const size_t clen = sizeof(cstr) / sizeof(cstr[0]);
+  const size_t wlen = sizeof(wstr) / sizeof(wstr[0]);
+
+  const int loops = 2 * BUFSIZ / wlen;
+  locale loc = locale("se_NO.UTF-8");
+
+  FILE* file = fopen(name, "w");
+  for (int i = 0; i < loops; ++i)
+    fwrite(cstr, 1, clen, file);
+  fclose(file);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.open(name, ios_base::in);
+
+  pos_type p1 = fb.pubseekoff(0, ios_base::cur);
+  pos_type end = fb.pubseekoff(0, ios_base::end);
+  pos_type beg = fb.pubseekoff(0, ios_base::beg);
+  VERIFY( p1 == beg );
+
+  const size_t limit = wlen * loops;
+  for (size_t index = 0; index < limit; ++index)
+    {
+      // Call seekoff at pseudo-random intervals.
+      if (index % 5 == 0 || index % 7 == 0)
+	{
+	  pos_type p2 = fb.pubseekoff(0, ios_base::cur);
+	  VERIFY( p2 != pos_type(-1) );
+	}
+      int_type c1 = fb.sbumpc();
+      VERIFY( c1 != eof );
+      VERIFY( static_cast<wchar_t>(c1) == wstr[index % wlen] );
+    }
+
+  pos_type p3 = fb.pubseekoff(0, ios_base::cur);
+  VERIFY( p3 == end );
+
+  int_type c2 = fb.sbumpc();
+  VERIFY( c2 == eof );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/11543.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/11543.cc
new file mode 100644
index 000000000..fd0c19ea3
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/11543.cc
@@ -0,0 +1,141 @@
+// Copyright (C) 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+struct MyState
+{
+};
+
+struct MyCharTraits : std::char_traits<wchar_t>
+{
+  typedef std::fpos<MyState> pos_type;
+  typedef MyState state_type;
+};
+
+namespace std
+{
+  template <>
+    class codecvt<wchar_t, char, MyState> :
+      public locale::facet, public codecvt_base
+    {
+    public:
+      typedef wchar_t intern_type;
+      typedef char extern_type;
+      typedef MyState state_type;
+    
+      explicit codecvt(size_t refs = 0)
+      : locale::facet(refs) { }
+    
+      result out(state_type& state, const intern_type* from,
+		 const intern_type* from_end,  const intern_type*& from_next,
+		 extern_type* to, extern_type* to_limit,
+		 extern_type*& to_next) const
+      { return do_out(state, from, from_end, from_next,
+		      to, to_limit, to_next); }
+
+      result unshift(state_type& state, extern_type* to, extern_type* to_limit,
+		     extern_type*& to_next) const
+      { return do_unshift(state, to, to_limit, to_next); }
+
+      result in(state_type& state, const extern_type* from,
+		const extern_type* from_end, const extern_type*& from_next,
+		intern_type* to, intern_type* to_limit,
+		intern_type*& to_next) const
+      { return do_in(state, from, from_end, from_next,
+		     to, to_limit, to_next); }
+
+      int encoding() const throw()
+      { return do_encoding(); }
+      
+      bool always_noconv() const throw()
+      { return do_always_noconv(); }
+
+      int length(state_type& state, const extern_type* from,
+		 const extern_type* end, size_t max) const
+      { return do_length(state, from, end, max); }
+
+      int max_length() const throw()
+      { return do_max_length(); }
+    
+      static locale::id id;
+    
+    protected:
+      virtual ~codecvt();
+
+      virtual result do_out(state_type&, const intern_type*,
+			    const intern_type*, const intern_type*&,
+			    extern_type*, extern_type*, extern_type*&) const
+      { return error; }
+
+      virtual result do_in(state_type&, const extern_type*, const extern_type*,
+			   const extern_type*&, intern_type*, intern_type*,
+			   intern_type*&) const
+      { return error; }
+
+      virtual result do_unshift(state_type&, extern_type*, extern_type*,
+				extern_type*&) const
+      { return noconv; }
+
+      virtual int do_encoding() const throw()
+      { return 1; }
+
+      virtual bool do_always_noconv() const throw()
+      { return false; }
+
+      virtual int do_length(state_type&, const extern_type* from,
+			    const extern_type* end, size_t max) const
+      {
+	size_t len = end - from;
+	return std::min(max, len);
+      }
+
+      virtual int do_max_length() const throw()
+      { return 1; }
+    };
+  
+  locale::id codecvt<wchar_t, char, MyState>::id;
+
+  codecvt<wchar_t, char, MyState>::~codecvt()
+  { }
+}
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  std::locale loc(std::locale::classic(),
+		  new std::codecvt<wchar_t, char, MyState>);
+  std::basic_filebuf<wchar_t, MyCharTraits> fb;
+  fb.pubimbue(loc);
+  fb.open("tmp_11543", std::ios_base::out);
+  VERIFY( fb.is_open() );
+  MyCharTraits::pos_type pos = fb.pubseekoff(0, std::ios_base::beg);
+  VERIFY( pos != MyCharTraits::pos_type(MyCharTraits::off_type(-1)) );
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-1.cc
new file mode 100644
index 000000000..b889f1bf5
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-1.cc
@@ -0,0 +1,78 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(L'a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-2.cc
new file mode 100644
index 000000000..d38952586
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-2.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(L'a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-3.cc
new file mode 100644
index 000000000..4057cd418
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-3.cc
@@ -0,0 +1,78 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift(),
+// but only if writing
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( !cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-4.cc
new file mode 100644
index 000000000..c04b4e79b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-4.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekoff() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekoff_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  fb.sputc(L'a');
+  fb.pubsync(); // Does not call unshift()
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekoff(0, ios_base::cur);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc
new file mode 100644
index 000000000..cc9c4e22a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc
@@ -0,0 +1,90 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-09-08  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Check that basic_filebuf::seekoff handles UTF-8 when open for input and
+// output.
+void test02()
+{
+  using namespace std;
+  typedef wfilebuf::int_type int_type;
+  bool test __attribute__((unused)) = true;
+  const char name[] = "tmp_seekoff-2.tst";
+
+  locale loc = locale("se_NO.UTF-8");
+
+  const size_t size = 10;
+  wchar_t buf[size];
+  streamsize n;
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+
+  n = fb.sputn(L"\xa0st", 3);
+  VERIFY( n == 3 );
+  
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 2);
+  VERIFY( n == 2 );
+  VERIFY( !wmemcmp(buf, L"\xa0s", 2) );
+
+  fb.pubseekoff(0, ios_base::cur);
+  n = fb.sputn(L"\xb2R", 2);
+  VERIFY( n == 2 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 4 );
+  VERIFY( !wmemcmp(buf, L"\xa0s\xb2R", 4) );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sputn(L"\x90m\x92n\x94", 5);
+  VERIFY( n == 5 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 2);
+  VERIFY( n == 2 );
+  VERIFY( !wmemcmp(buf, L"\x90m", 2) );
+
+  fb.pubseekoff(0, ios_base::end);
+  n = fb.sputn(L"I\xbfJ", 3);
+  VERIFY( n == 3 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 8 );
+  VERIFY( !wmemcmp(buf, L"\x90m\x92n\x94I\xbfJ", 8) );
+
+  fb.close();
+}
+
+int main()
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/3.cc
new file mode 100644
index 000000000..435ebcc3e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/3.cc
@@ -0,0 +1,51 @@
+// Copyright (C) 2003, 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test03()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  const char* name = "tmp_seekoff_3";
+
+  wfilebuf fb;
+
+  fb.open(name, ios_base::out);
+  fb.sputc(0xf001);
+
+  try
+    {
+      // seekoff should flush the output sequence, which will fail
+      // if the output buffer contains illegal characters.
+      fb.pubseekoff(0, ios_base::cur);
+      VERIFY( false );
+    }
+  catch (std::exception&)
+    {
+    }
+}
+
+int main()
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/4.cc
new file mode 100644
index 000000000..245f18f48
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/4.cc
@@ -0,0 +1,94 @@
+// { dg-require-fileio "" }
+
+// Copyright (C) 2010, 2011 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <cwchar>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  typedef wfilebuf::pos_type pos_type;
+  const char name[] = "tmp_seekoff-4.tst";
+
+  const size_t size = 12;
+  wchar_t buf[size];
+  streamsize n;
+
+  wfilebuf fb;
+  fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+
+  n = fb.sputn(L"abcd", 4);
+  VERIFY( n == 4 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 3);
+  VERIFY( n == 3 );
+  VERIFY( !wmemcmp(buf, L"abc", 3) );
+
+  // Check read => write without pubseekoff(0, ios_base::cur)
+
+  n = fb.sputn(L"ef", 2);
+  VERIFY( n == 2 );
+
+  fb.pubseekoff(0, ios_base::beg);
+
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 5 );
+  VERIFY( !wmemcmp(buf, L"abcef", 5) );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sputn(L"gh", 2);
+  VERIFY( n == 2 );
+  
+  // Check write => read without pubseekoff(0, ios_base::cur)
+
+  n = fb.sgetn( buf, 3 );
+  VERIFY( !memcmp(buf, L"cef", 3) );
+
+  n = fb.sputn(L"ijkl", 4);
+  VERIFY( n == 4 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 2);
+  VERIFY( n == 2 );
+  VERIFY( !wmemcmp(buf, L"gh", 2) );
+
+  fb.pubseekoff(0, ios_base::end);
+  n = fb.sputn(L"mno", 3);
+  VERIFY( n == 3 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 12 );
+  VERIFY( !wmemcmp(buf, L"ghcefijklmno", 12) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/9875_seekoff.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/9875_seekoff.cc
new file mode 100644
index 000000000..312386a24
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/9875_seekoff.cc
@@ -0,0 +1,99 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <algorithm>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, mbstate_t>
+{
+protected:
+  virtual std::codecvt_base::result
+  do_out(std::mbstate_t&, const wchar_t* from, const wchar_t* from_end,
+	 const wchar_t*& from_next, char* to, char* to_end,
+	 char*& to_next) const
+  {
+    std::size_t from_len = from_end - from;
+    std::size_t to_len = (to_end - to) / sizeof(wchar_t);
+    std::size_t len = std::min(from_len, to_len);
+    std::memcpy(to, from, len * sizeof(wchar_t));
+    from_next = from + len;
+    to_next = to + len * sizeof(wchar_t);
+    return from_next == from_end ? std::codecvt_base::ok :
+           std::codecvt_base::partial;
+  }
+
+  virtual std::codecvt_base::result
+  do_in(std::mbstate_t&, const char* from, const char* from_end,
+	const char*& from_next, wchar_t* to, wchar_t* to_end,
+	wchar_t*& to_next) const
+  {
+    std::size_t from_len =
+      (from_end - from) / sizeof(wchar_t);
+    std::size_t to_len = to_end - to;
+    std::size_t len = std::min(from_len, to_len);
+    std::memcpy(to, from, len * sizeof(wchar_t));
+    from_next = from + len * sizeof(wchar_t);
+    to_next = to + len;
+    return from_next == from_end ? std::codecvt_base::ok :
+           std::codecvt_base::partial;
+  }
+  
+  virtual std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char*, char*, char*&) const
+  { return std::codecvt_base::noconv; }
+  
+  virtual int do_encoding() const throw() { return sizeof(wchar_t); }
+  virtual bool do_always_noconv() const throw() { return false; }
+  
+  virtual int
+  do_length(std::mbstate_t&, const char* from, const char* end,
+	    std::size_t max)
+  {
+    std::size_t len = (end - from) / sizeof(wchar_t);
+    return std::min(len, max) * sizeof(wchar_t);
+  }
+  
+  virtual int do_max_length() const throw() { return sizeof(wchar_t); }
+};
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  
+  // seekoff
+  wfilebuf fb;
+  fb.pubimbue(locale(locale::classic(), new Cvt));
+  fb.open("tmp_9875_seekoff", ios_base::out | ios_base::in | ios_base::trunc);
+  fb.sputn(L"0123456789", 10);
+  fb.pubseekoff(-3, ios_base::cur);
+  VERIFY( fb.sgetc() == L'7' );
+  fb.pubseekoff(-3, ios_base::cur);
+  VERIFY( fb.sgetc() == L'4' );
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/10132-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/10132-3.cc
new file mode 100644
index 000000000..34d437925
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/10132-3.cc
@@ -0,0 +1,54 @@
+// 2003-04-24 bkoz
+
+// Copyright (C) 2003, 2004, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.1 - Template class basic_filebuf 
+// NB: This file is for testing basic_filebuf with NO OTHER INCLUDES.
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/10132, add on
+void test07()
+{
+  bool test __attribute__((unused)) = true;
+  typedef std::basic_filebuf<__gnu_test::pod_ushort> gnu_filebuf;
+  
+  try
+    { 
+      // Need codecvt facet for width argument in seekpos.
+      gnu_filebuf obj;
+      obj.pubseekpos(0);
+    }
+  catch(std::exception& obj)
+    { 
+      test = false; 
+      VERIFY( test );
+    }
+}
+
+int main() 
+{
+  test07();
+  return 0;
+}
+
+
+
+// more surf!!!
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-1.cc
new file mode 100644
index 000000000..ffe5aa726
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-1.cc
@@ -0,0 +1,67 @@
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+  traits_type::pos_type pos = fb.pubseekoff(0, ios_base::cur);
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+
+  // Check that seekpos restores the state correctly
+  fb.pubseekpos(pos);
+
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-2.cc
new file mode 100644
index 000000000..8b7050965
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-2.cc
@@ -0,0 +1,82 @@
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out | ios_base::trunc);
+  fb.sputc(pod_uchar::from<char>('b'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>(0xfc));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+
+  fb.close();
+  fb.open(name, ios_base::in);
+
+  fb.sbumpc();
+  fb.sbumpc();
+  traits_type::pos_type pos1 = fb.pubseekoff(0, ios_base::cur);
+  fb.sbumpc();
+  fb.sbumpc();
+
+  // Check that seekpos returns the correct state
+  traits_type::pos_type pos2 = fb.pubseekpos(pos1);
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+  fb.sbumpc();
+
+  fb.pubseekpos(pos2);
+  c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-3.cc
new file mode 100644
index 000000000..79337d381
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/12790-3.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_character.h>
+
+// libstdc++/12790
+void test01()
+{
+  using namespace std;
+  using __gnu_test::pod_uchar;
+  typedef basic_filebuf<pod_uchar>::traits_type traits_type;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  locale loc(locale::classic(),
+	     new codecvt<traits_type::char_type, char,
+	     traits_type::state_type>);
+
+  basic_filebuf<pod_uchar> fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+  fb.sputc(pod_uchar::from<char>('b'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+  fb.sputc(pod_uchar::from<char>('c'));
+  fb.sputc(pod_uchar::from<char>(0xff));
+
+  fb.pubseekoff(0, ios_base::beg);
+  fb.sbumpc();
+  fb.sbumpc();
+  traits_type::pos_type pos = fb.pubseekoff(0, ios_base::cur);
+  fb.sbumpc();
+  fb.sbumpc();
+
+  // Check that seekoff sets the current state for output
+  fb.pubseekpos(pos);
+
+  fb.sputc(pod_uchar::from<char>('a'));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+  fb.sputc(pod_uchar::from<char>(0));
+  
+  fb.pubseekpos(pos);
+
+  traits_type::int_type c = fb.sbumpc();
+  VERIFY( c != traits_type::eof() );
+  VERIFY( traits_type::eq(traits_type::to_char_type(c),
+			  pod_uchar::from<char>('a')) );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-in.cc
new file mode 100644
index 000000000..da5a80b4b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-in.cc
@@ -0,0 +1,103 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekpos.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  pos_type pt_3;
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekpos
+  // pubseekpos(pos_type sp, ios_base::openmode)
+  // alters the stream position to sp
+
+  // in 
+  {
+    constraint_filebuf fb;
+    fb.open(name_01, ios_base::in);
+    VERIFY( !fb.write_position() );
+
+    // beg
+    pt_1 = fb.pubseekoff(78, ios_base::beg);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == 't' );
+
+    // cur
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c2 = fb.sputc('\n'); //test current out pointer
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c3 = fb.sgetc();
+    fb.pubsync(); //resets pointers
+    pt_2 = fb.pubseekpos(pt_1);
+    off_2 = off_type(pt_2);
+    VERIFY( off_1 == off_2 );
+    c3 = fb.snextc(); //current in pointer +1
+    VERIFY( c2 == traits_type::eof() );
+    VERIFY( c2 != c3 );
+
+    // end
+    pt_1 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > off_2 );
+    fb.sputn("\nof the wonderful things he does!!\nok", 37);
+    fb.pubsync();
+    VERIFY( !fb.write_position() );
+    fb.close();
+    VERIFY( !fb.is_open() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-io.cc
new file mode 100644
index 000000000..c90de5e31
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-io.cc
@@ -0,0 +1,103 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekpos-1io.tst"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+
+  bool test __attribute__((unused)) = true;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  pos_type pt_3;
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekpos
+  // pubseekpos(pos_type sp, ios_base::openmode)
+  // alters the stream position to sp
+
+  // in | out
+  {
+    constraint_filebuf fb;
+    fb.open(name_01, ios_base::out | ios_base::in);
+    VERIFY( !fb.write_position() );
+    VERIFY( !fb.read_position() );
+
+    // beg
+    pt_1 = fb.pubseekoff(78, ios_base::beg);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == 't' );
+
+    // cur
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c2 = fb.sputc('\n'); //test current out pointer
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c3 = fb.sgetc();
+    fb.pubsync(); //resets pointers
+    pt_2 = fb.pubseekpos(pt_1);
+    off_2 = off_type(pt_2);
+    VERIFY( off_1 == off_2 );
+    c3 = fb.snextc(); //current in pointer +1
+    VERIFY( c2 == c3 );
+
+    // end
+    pt_1 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > off_2 );
+    fb.sputn("\nof the wonderful things he does!!\nok", 37);
+    fb.pubsync();
+    VERIFY( fb.write_position() );
+    VERIFY( !fb.read_position() );
+    fb.close();
+    VERIFY( !fb.is_open() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-out.cc
new file mode 100644
index 000000000..0b596a451
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/1-out.cc
@@ -0,0 +1,105 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekpos-1out.tst"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  pos_type pt_3;
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekpos
+  // pubseekpos(pos_type sp, ios_base::openmode)
+  // alters the stream position to sp
+
+  // out
+  {
+    constraint_filebuf fb;
+    fb.open(name_01, ios_base::out);
+    VERIFY( !fb.write_position() );
+    VERIFY( !fb.read_position() );
+
+    // beg
+    pt_1 = fb.pubseekoff(78, ios_base::beg);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == traits_type::eof() );
+
+    // cur
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c2 = fb.sputc('\n'); //test current out pointer
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c3 = fb.sgetc();
+    fb.pubsync(); //resets pointers
+    pt_2 = fb.pubseekpos(pt_1);
+    off_2 = off_type(pt_2);
+    VERIFY( off_1 == off_2 );
+    c3 = fb.snextc(); //current in pointer +1
+    VERIFY( c2 != c3 );
+    VERIFY( c3 == traits_type::eof() );
+
+    // end
+    pt_1 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > off_2 );
+    fb.sputn("\nof the wonderful things he does!!\nok", 37);
+    fb.pubsync();
+    VERIFY( fb.write_position() );
+    VERIFY( !fb.read_position() );
+    fb.close();
+    VERIFY( !fb.is_open() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-1.cc
new file mode 100644
index 000000000..1a024941f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-1.cc
@@ -0,0 +1,81 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+  fb.sputc('a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-2.cc
new file mode 100644
index 000000000..b0085e29e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-2.cc
@@ -0,0 +1,82 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+  fb.sputc('a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-3.cc
new file mode 100644
index 000000000..0eb3ecf80
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-3.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift(),
+// but only if writing
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( !cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-4.cc
new file mode 100644
index 000000000..506482bd6
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/12790-4.cc
@@ -0,0 +1,82 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<char, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  filebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+  fb.sputc('a');
+  fb.pubsync(); // Does not call unshift()
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-in.cc
new file mode 100644
index 000000000..782fb6bb8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-in.cc
@@ -0,0 +1,104 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekpos.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  pos_type pt_3;
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekpos
+  // pubseekpos(pos_type sp, ios_base::openmode)
+  // alters the stream position to sp
+
+  // in 
+  {
+    constraint_filebuf fb;
+    fb.pubsetbuf(0, 0);
+    fb.open(name_01, ios_base::in);
+    VERIFY( fb.unbuffered() );
+
+    // beg
+    pt_1 = fb.pubseekoff(78, ios_base::beg);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == 't' );
+
+    // cur
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c2 = fb.sputc('\n'); //test current out pointer
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c3 = fb.sgetc();
+    fb.pubsync(); //resets pointers
+    pt_2 = fb.pubseekpos(pt_1);
+    off_2 = off_type(pt_2);
+    VERIFY( off_1 == off_2 );
+    c3 = fb.snextc(); //current in pointer +1
+    VERIFY( c2 == traits_type::eof() );
+    VERIFY( c2 != c3 );
+
+    // end
+    pt_1 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > off_2 );
+    fb.sputn("\nof the wonderful things he does!!\nok", 37);
+    fb.pubsync();
+    VERIFY( fb.unbuffered() );
+    fb.close();
+    VERIFY( !fb.is_open() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-io.cc
new file mode 100644
index 000000000..4916d6059
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-io.cc
@@ -0,0 +1,102 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekpos-2io.tst"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+
+  bool test __attribute__((unused)) = true;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  pos_type pt_3;
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekpos
+  // pubseekpos(pos_type sp, ios_base::openmode)
+  // alters the stream position to sp
+
+  // in | out
+  {
+    constraint_filebuf fb;
+    fb.pubsetbuf(0, 0);
+    fb.open(name_01, ios_base::out | ios_base::in);
+    VERIFY( fb.unbuffered() );
+
+    // beg
+    pt_1 = fb.pubseekoff(78, ios_base::beg);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == 't' );
+
+    // cur
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c2 = fb.sputc('\n'); //test current out pointer
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c3 = fb.sgetc();
+    fb.pubsync(); //resets pointers
+    pt_2 = fb.pubseekpos(pt_1);
+    off_2 = off_type(pt_2);
+    VERIFY( off_1 == off_2 );
+    c3 = fb.snextc(); //current in pointer +1
+    VERIFY( c2 == c3 );
+
+    // end
+    pt_1 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > off_2 );
+    fb.sputn("\nof the wonderful things he does!!\nok", 37);
+    fb.pubsync();
+    VERIFY( fb.unbuffered() );
+    fb.close();
+    VERIFY( !fb.is_open() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-out.cc
new file mode 100644
index 000000000..9031bca6c
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/2-out.cc
@@ -0,0 +1,104 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "seekpos-2out.tst"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::pos_type 	pos_type;
+  typedef filebuf::off_type 	off_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  int_type c1;
+  int_type c2;
+  int_type c3;
+
+  pos_type pt_1(off_type(-1));
+  pos_type pt_2(off_type(0));
+  pos_type pt_3;
+  off_type off_1 = 0;
+  off_type off_2 = 0;
+
+  // seekpos
+  // pubseekpos(pos_type sp, ios_base::openmode)
+  // alters the stream position to sp
+
+  // out
+  {
+    constraint_filebuf fb;
+    fb.pubsetbuf(0, 0);
+    fb.open(name_01, ios_base::out);
+    VERIFY( fb.unbuffered() );
+
+    // beg
+    pt_1 = fb.pubseekoff(78, ios_base::beg);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > 0 );
+    c1 = fb.snextc(); //current in pointer +1
+    VERIFY( c1 == traits_type::eof() );
+
+    // cur
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c2 = fb.sputc('\n'); //test current out pointer
+    pt_3 = fb.pubseekoff(0, ios_base::cur);
+    fb.pubseekpos(pt_3);
+    c3 = fb.sgetc();
+    fb.pubsync(); //resets pointers
+    pt_2 = fb.pubseekpos(pt_1);
+    off_2 = off_type(pt_2);
+    VERIFY( off_1 == off_2 );
+    c3 = fb.snextc(); //current in pointer +1
+    VERIFY( c2 != c3 );
+    VERIFY( c3 == traits_type::eof() );
+
+    // end
+    pt_1 = fb.pubseekoff(0, ios_base::end);
+    off_1 = off_type(pt_1);
+    VERIFY( off_1 > off_2 );
+    fb.sputn("\nof the wonderful things he does!!\nok", 37);
+    fb.pubsync();
+    VERIFY( fb.unbuffered() );
+    fb.close();
+    VERIFY( !fb.is_open() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-in.cc
new file mode 100644
index 000000000..278d39e72
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-in.cc
@@ -0,0 +1,63 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.7.1.3 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test02(std::filebuf& in, bool pass)
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  typedef streambuf::pos_type pos_type;
+  typedef streambuf::off_type off_type;
+  pos_type bad = pos_type(off_type(-1));
+  pos_type p = 0;
+
+  // seekpos
+  p = in.pubseekpos(0, ios_base::in);
+  VERIFY( pass == (p != bad) );
+
+  p = in.pubseekpos(0, ios_base::out);
+  VERIFY( pass == (p != bad) );  // See libstdc++/12232
+
+  p = in.pubseekpos(0); 
+  VERIFY( pass == (p != bad) );
+}
+
+const char name_01[] = "filebuf_virtuals-1.tst"; // file with data in it
+const char name_03[] = "filebuf_members-1.tst"; // empty file
+
+int main() 
+{
+  using namespace std;
+
+  filebuf in1;
+  in1.open(name_01, ios_base::in);
+  filebuf in2;
+  filebuf in3;
+  in3.open(name_03, ios_base::in);
+  test02(in1, true);
+  test02(in2, false);
+  test02(in3, true);
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-io.cc
new file mode 100644
index 000000000..3f37a266a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-io.cc
@@ -0,0 +1,66 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.7.1.3 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test02(std::filebuf& in, bool pass)
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  typedef streambuf::pos_type pos_type;
+  typedef streambuf::off_type off_type;
+  pos_type bad = pos_type(off_type(-1));
+  pos_type p = 0;
+
+  // seekpos
+  p = in.pubseekpos(0, ios_base::in);
+  if (pass)
+    VERIFY( p != bad );
+
+  p = in.pubseekpos(0, ios_base::out); 
+  if (pass)
+    VERIFY( p != bad );
+
+  p = in.pubseekpos(0); 
+  if (pass)
+    VERIFY( p != bad );
+}
+
+const char name_01[] = "filebuf_virtuals-1.tst"; // file with data in it
+const char name_03[] = "filebuf_members-1.tst"; // empty file
+
+int main() 
+{
+  using namespace std;
+
+  filebuf in1;
+  in1.open(name_01, ios_base::in | ios_base::out);
+  filebuf in2;
+  filebuf in3;
+  in3.open(name_03, ios_base::in | ios_base::out);
+  test02(in1, true);
+  test02(in2, false);
+  test02(in3, true);
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-out.cc
new file mode 100644
index 000000000..07bdc0cae
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/char/3-out.cc
@@ -0,0 +1,63 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.7.1.3 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test02(std::filebuf& in, bool pass)
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+  typedef streambuf::pos_type pos_type;
+  typedef streambuf::off_type off_type;
+  pos_type bad = pos_type(off_type(-1));
+  pos_type p = 0;
+
+  // seekpos
+  p = in.pubseekpos(0, ios_base::in);
+  VERIFY( pass == (p != bad) );  // See libstdc++/12232
+
+  p = in.pubseekpos(0, ios_base::out); 
+  VERIFY( pass == (p != bad) );
+
+  p = in.pubseekpos(0);
+  VERIFY( pass == (p != bad) );
+}
+
+const char name_01[] = "filebuf_virtuals-1.tst"; // file with data in it
+const char name_03[] = "filebuf_members-1.tst"; // empty file
+
+int main() 
+{
+  using namespace std;
+
+  filebuf out1;
+  out1.open(name_01, ios_base::out);
+  filebuf out2;
+  filebuf out3;
+  out3.open(name_03, ios_base::out);
+  test02(out1, true);
+  test02(out2, false);
+  test02(out3, true);
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/1.cc
new file mode 100644
index 000000000..320938319
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/1.cc
@@ -0,0 +1,51 @@
+// Copyright (C) 2003, 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  const char* name = "tmp_seekpos_1";
+
+  wfilebuf fb;
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+  fb.sputc(0xf001);
+
+  try
+    {
+      fb.pubseekpos(pos);
+      VERIFY( false );
+    }
+  catch (std::exception&)
+    {
+    }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-1.cc
new file mode 100644
index 000000000..55325875a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-1.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+  fb.sputc(L'a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-2.cc
new file mode 100644
index 000000000..e939050a4
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-2.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+  fb.sputc(L'a');
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-3.cc
new file mode 100644
index 000000000..a1afdcad2
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-3.cc
@@ -0,0 +1,79 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift(),
+// but only if writing
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( !cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-4.cc
new file mode 100644
index 000000000..57a9a3c02
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/12790-4.cc
@@ -0,0 +1,80 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
+{
+public:
+  mutable bool unshift_called;
+
+  Cvt()
+  : unshift_called(false)
+  { }
+
+protected:
+  bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  int
+  do_encoding() const throw()
+  { return -1; }
+
+  std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
+  {
+    unshift_called = true;
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+};
+
+// libstdc++/12790
+// basic_filebuf::seekpos() should call codecvt::unshift()
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_seekpos_12790";
+
+  Cvt* cvt = new Cvt;
+  locale loc(locale::classic(), cvt);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+
+  fb.open(name, ios_base::out);
+  streampos pos = fb.pubseekoff(0, ios_base::beg);
+  fb.sputc(L'a');
+  fb.pubsync(); // Does not call unshift()
+
+  VERIFY( !cvt->unshift_called );
+  fb.pubseekpos(pos);
+  VERIFY( cvt->unshift_called );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/9874.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/9874.cc
new file mode 100644
index 000000000..e011f875d
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/9874.cc
@@ -0,0 +1,139 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-10-07  Petur Runolfsson  <peturr02@ru.is>
+//
+// Copyright (C) 2003, 2004, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <vector>
+#include <utility>
+#include <testsuite_hooks.h>
+
+// libstdc++/9874
+void test01()
+{
+  using namespace std;
+  typedef wfilebuf::pos_type pos_type;
+  typedef wfilebuf::int_type int_type;
+  typedef vector<pair<pos_type, size_t> > vec_type;
+
+  bool test __attribute__((unused)) = true;
+  const char name[] = "tmp_seekpos-9874.tst";
+  const int_type eof = wfilebuf::traits_type::eof();
+
+  const char cstr[] =
+    "\x1\x2\x3\x4\x5\x6\x7\x8\x9\xa\xb\xc\xd\xe\xf\x10\x11\x12\x13"
+    "\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20!\"#$%&"
+    "'()*+,-./0123456789:;<=>?@}~\x7f\xc2\x80\xc2\x81\xc2\x82\xc2"
+    "\x83\xc2\x84\xc2\x85\xc2\x86\xc2\x87\xc2\x88\xc2\x89\xc2\x8a"
+    "\xc2\x8b\xc2\x8c\xc2\x8d\xc2\x8e\xc2\x8f\xc2\x90\xc2\x91\xc2"
+    "\x92\xc2\x93\xc2\x94\xc2\x95\xc2\x96\xc2\x97\xc2\x98\xc2\x99"
+    "\xc2\x9a\xc2\x9b\xc2\x9c\xc3\xba\xc3\xbb\xc3\xbc\xc3\xbd\xc3"
+    "\xbe\xc3\xbf\xc4\x80\xc4\x81\xc4\x82\xc4\x83\xc4\x84\xc4\x85"
+    "\xc4\x86\xc4\x87\xc4\x88\xc4\x89\xc4\x8a\xc4\x8b\xc4\x8c\xc4"
+    "\x8d\xc4\x8e\xc4\x8f\xc4\x90\xc4\x91\xc4\x92\xc4\x93\xc4\x94"
+    "\xc4\x95\xc4\x96\xc4\x97\xc4\x98\xc4\x99\xdf\xb8\xdf\xb9\xdf"
+    "\xba\xdf\xbb\xdf\xbc\xdf\xbd\xdf\xbe\xdf\xbf\xe0\xa0\x80\xe0"
+    "\xa0\x81\xe0\xa0\x82\xe0\xa0\x83\xe0\xa0\x84\xe0\xa0\x85\xe0"
+    "\xa0\x86\xe0\xa0\x87\xe0\xa0\x88\xe0\xa0\x89\xe0\xa0\x8a\xe0"
+    "\xa0\x8b\xe0\xa0\x8c\xe0\xa0\x8d\xe0\xa0\x8e\xe0\xa0\x8f\xe0"
+    "\xa0\x90\xe0\xa0\x91\xe0\xa0\x92\xe0\xa0\x93\xe0\xa0\x94\xe0"
+    "\xa0\x95\xe0\xa0\x96\xe0\xa0\x97\x1\x2\x4\x8\x10\x20@\xc2\x80"
+    "\xc4\x80\xc8\x80\xd0\x80\xe0\xa0\x80\xe1\x80\x80\xe2\x80\x80"
+    "\xe4\x80\x80\xe8\x80\x80\xf0\x90\x80\x80\xf0\xa0\x80\x80\xf1"
+    "\x80\x80\x80\xf2\x80\x80\x80\xf4\x80\x80\x80\xf8\x88\x80\x80"
+    "\x80\xf8\x90\x80\x80\x80\xf8\xa0\x80\x80\x80\xf9\x80\x80\x80"
+    "\x80\xfa\x80\x80\x80\x80\xfc\x84\x80\x80\x80\x80\xfc\x88\x80"
+    "\x80\x80\x80\xfc\x90\x80\x80\x80\x80\xfc\xa0\x80\x80\x80\x80"
+    "\xfd\x80\x80\x80\x80\x80";
+
+  const wchar_t wstr[] = {
+    0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc,
+    0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, L'!',
+    L'"', L'#', L'$', L'%', L'&', L'\'', L'(', L')', L'*', L'+',
+    L',', L'-', L'.', L'/', L'0', L'1', L'2', L'3', L'4', L'5',
+    L'6', L'7', L'8', L'9', L':', L';', L'<', L'=', L'>', L'?',
+    L'@', L'}', L'~', 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
+    0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+    0x9a, 0x9b, 0x9c, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 0x100,
+    0x101, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107, 0x108, 0x109,
+    0x10a, 0x10b, 0x10c, 0x10d, 0x10e, 0x10f, 0x110, 0x111, 0x112,
+    0x113, 0x114, 0x115, 0x116, 0x117, 0x118, 0x119, 0x7f8, 0x7f9,
+    0x7fa, 0x7fb, 0x7fc, 0x7fd, 0x7fe, 0x7ff, 0x800, 0x801, 0x802,
+    0x803, 0x804, 0x805, 0x806, 0x807, 0x808, 0x809, 0x80a, 0x80b,
+    0x80c, 0x80d, 0x80e, 0x80f, 0x810, 0x811, 0x812, 0x813, 0x814,
+    0x815, 0x816, 0x817, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, L'@',
+    0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000,
+    0x10000, 0x20000, 0x40000, 0x80000, 0x100000, 0x200000, 0x400000,
+    0x800000, 0x1000000, 0x2000000, 0x4000000, 0x8000000, 0x10000000,
+    0x20000000, 0x40000000, 0x0
+  };
+
+  const size_t clen = sizeof(cstr) / sizeof(cstr[0]);
+  const size_t wlen = sizeof(wstr) / sizeof(wstr[0]);
+
+  const int loops = 2 * BUFSIZ / wlen;
+  locale loc = locale("se_NO.UTF-8");
+
+  FILE* file = fopen(name, "w");
+  for (int i = 0; i < loops; ++i)
+    fwrite(cstr, 1, clen, file);
+  fclose(file);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.open(name, ios_base::in);
+
+  vec_type vec;
+
+  const size_t limit = wlen * loops;
+  for (size_t index = 0; index < limit; ++index)
+    {
+      // Call seekoff at pseudo-random intervals.
+      if (index % 5 == 0 || index % 7 == 0)
+	{
+	  pos_type p1 = fb.pubseekoff(0, ios_base::cur);
+	  VERIFY( p1 != pos_type(-1) );
+	  vec.push_back(make_pair(p1, index));
+	}
+      int_type c1 = fb.sbumpc();
+      VERIFY( c1 != eof );
+    }
+
+  for (vec_type::iterator it = vec.begin(); it != vec.end(); ++it)
+    {
+      pos_type p2 = fb.pubseekpos(it->first);
+      VERIFY( p2 == it->first );
+      int_type c2 = fb.sbumpc();
+      VERIFY( c2 != eof );
+      VERIFY( static_cast<wchar_t>(c2) == wstr[it->second % wlen] );
+    }
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/9875_seekpos.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/9875_seekpos.cc
new file mode 100644
index 000000000..501ce1fda
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekpos/wchar_t/9875_seekpos.cc
@@ -0,0 +1,111 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <algorithm>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+class Cvt : public std::codecvt<wchar_t, char, mbstate_t>
+{
+protected:
+  virtual std::codecvt_base::result
+  do_out(std::mbstate_t&, const wchar_t* from, const wchar_t* from_end,
+	 const wchar_t*& from_next, char* to, char* to_end,
+	 char*& to_next) const
+  {
+    std::size_t from_len = from_end - from;
+    std::size_t to_len = (to_end - to) / sizeof(wchar_t);
+    std::size_t len = std::min(from_len, to_len);
+    std::memcpy(to, from, len * sizeof(wchar_t));
+    from_next = from + len;
+    to_next = to + len * sizeof(wchar_t);
+    return from_next == from_end ? std::codecvt_base::ok :
+           std::codecvt_base::partial;
+  }
+
+  virtual std::codecvt_base::result
+  do_in(std::mbstate_t&, const char* from, const char* from_end,
+	const char*& from_next, wchar_t* to, wchar_t* to_end,
+	wchar_t*& to_next) const
+  {
+    std::size_t from_len =
+      (from_end - from) / sizeof(wchar_t);
+    std::size_t to_len = to_end - to;
+    std::size_t len = std::min(from_len, to_len);
+    std::memcpy(to, from, len * sizeof(wchar_t));
+    from_next = from + len * sizeof(wchar_t);
+    to_next = to + len;
+    return from_next == from_end ? std::codecvt_base::ok :
+           std::codecvt_base::partial;
+  }
+  
+  virtual std::codecvt_base::result
+  do_unshift(std::mbstate_t&, char*, char*, char*&) const
+  { return std::codecvt_base::noconv; }
+  
+  virtual int do_encoding() const throw() { return sizeof(wchar_t); }
+  virtual bool do_always_noconv() const throw() { return false; }
+  
+  virtual int
+  do_length(std::mbstate_t&, const char* from, const char* end,
+	    std::size_t max)
+  {
+    std::size_t len = (end - from) / sizeof(wchar_t);
+    return std::min(len, max) * sizeof(wchar_t);
+  }
+  
+  virtual int do_max_length() const throw() { return sizeof(wchar_t); }
+};
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  // seekpos
+  wfilebuf fb;
+  fb.pubimbue(locale(locale::classic(), new Cvt));
+  fb.open("tmp_9875_seekpos", ios_base::out | ios_base::in | ios_base::trunc);
+  fb.sputn(L"0123456789", 10);
+  
+  streampos p1 = fb.pubseekoff(0, ios_base::cur);
+  VERIFY( p1 != streampos(-1) );
+  fb.sputc(L'a');
+  
+  streampos p2 = fb.pubseekpos(p1);
+  VERIFY( p2 != streampos(-1) );
+  VERIFY( p2 == p1 );
+  VERIFY( fb.sgetc() == L'a' );
+  
+  fb.pubseekoff(0, ios_base::beg);
+  wchar_t buf[11];
+  streamsize s1 = fb.sgetn(buf, 11);
+  VERIFY( s1 == 11 );
+  VERIFY( !wmemcmp(buf, L"0123456789a", 11) );
+  
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/1.cc
new file mode 100644
index 000000000..42688e825
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/1.cc
@@ -0,0 +1,89 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class testbuf : public std::filebuf
+{
+public:
+
+  // Typedefs:
+  typedef std::filebuf base_type;
+  typedef base_type::traits_type traits_type;
+  typedef base_type::char_type char_type;
+
+  testbuf(): base_type() 
+  { _M_mode = (std::ios_base::in | std::ios_base::out); }
+
+  bool
+  check_pointers()
+  { 
+    bool test __attribute__((unused)) = true;
+    test = (!this->pbase());
+    test &= (!this->pptr());
+    return test;
+  }
+};
+
+const char name_01[] = "filebuf_virtuals-1.txt";
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  typedef std::filebuf::int_type 	int_type;
+  typedef std::filebuf::traits_type 	traits_type;
+  typedef std::filebuf::pos_type 	pos_type;
+  typedef std::filebuf::off_type 	off_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+
+  {
+    testbuf 				f_tmp;
+
+    // setbuf
+    // pubsetbuf(char_type* s, streamsize n)
+    f_tmp.pubsetbuf(0,0);
+    VERIFY( f_tmp.check_pointers() );
+  }
+
+  {
+    testbuf 				f_tmp;
+    
+    f_tmp.open(name_01, ios_base::out | ios_base::in);
+    f_tmp.sbumpc();
+    
+    // setbuf
+    // pubsetbuf(char_type* s, streamsize n)
+    f_tmp.pubsetbuf(0, 0);
+    VERIFY( f_tmp.check_pointers() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/12875-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/12875-1.cc
new file mode 100644
index 000000000..ed567de1b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/12875-1.cc
@@ -0,0 +1,58 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <cstdio>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+// libstdc++/12875
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  const char* name = "tmp_setbuf4";
+  static char buf[1024];
+  
+  FILE* out = fopen(name, "w");
+  fputs("Hello, world", out);
+  fclose(out);
+  
+  filebuf in;
+  in.open(name, ios_base::in);
+  char str[256];
+  streamsize r = in.sgetn(str, 6);
+  VERIFY( r == 6 );
+  VERIFY( !memcmp(str, "Hello,", 6) );
+  in.pubsetbuf(buf, 1024);
+  r = in.sgetn(str, 6);
+  VERIFY( r == 6 );
+  VERIFY( !memcmp(str, " world", 6) );
+  in.close();
+}
+
+// libstdc++/12875
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/12875-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/12875-2.cc
new file mode 100644
index 000000000..b736b1460
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/12875-2.cc
@@ -0,0 +1,56 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <cstdio>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+// libstdc++/12875
+void test02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  const char* name = "tmp_setbuf5";
+  static char buf[1024];
+  
+  filebuf out;
+  out.open(name, ios_base::out);
+  streamsize r = out.sputn("Hello,", 6);
+  VERIFY( r == 6 );
+  out.pubsetbuf(buf, 1024);
+  r = out.sputn(" world", 6);
+  VERIFY( r == 6 );
+  VERIFY( out.close() );
+  
+  FILE* in = fopen(name, "r");
+  char str[256];
+  VERIFY( fgets(str, 256, in) );
+  VERIFY( !strcmp(str, "Hello, world") );
+  fclose(in);
+}
+
+int main()
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/2.cc
new file mode 100644
index 000000000..768285d75
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/2.cc
@@ -0,0 +1,48 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  char buf[512];
+  const char* strlit = "how to tell a story and other essays: mark twain";
+  const size_t strlitsize = std::strlen(strlit);
+  filebuf fbuf;
+  fbuf.pubsetbuf(buf, 512);
+  fbuf.open("tmp_setbuf2", ios_base::out);
+  fbuf.sputn(strlit, strlitsize);
+  VERIFY( std::strncmp(strlit, buf, strlitsize) == 0 );
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/3.cc
new file mode 100644
index 000000000..bdb3989c3
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/setbuf/char/3.cc
@@ -0,0 +1,51 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <cstring>
+#include <testsuite_hooks.h>
+
+void test03()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  char buf[512];
+  const char* strlit = "how to tell a story and other essays: mark twain";
+  const size_t strlitsize = std::strlen(strlit);
+  filebuf fbuf01;
+  // NB: +2 otherwise sputn is optimized to a direct write,
+  // bypassing the buffer.
+  fbuf01.pubsetbuf(buf, strlitsize + 2);
+  fbuf01.open("tmp_setbuf3", ios_base::out);
+
+  fbuf01.sputn(strlit, strlitsize);
+  VERIFY( std::strncmp(strlit, buf, strlitsize) == 0 );
+}
+
+int main() 
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-in.cc
new file mode 100644
index 000000000..3defffccf
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-in.cc
@@ -0,0 +1,72 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sgetc()
+  // if read_cur not avail, return uflow(), else return *read_cur  
+
+  // in
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.open(name_01, ios::in);
+    VERIFY( !fb_01.write_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sgetc();
+    VERIFY( c1 == c2 );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sgetc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    VERIFY( c2 == ' ' );
+    VERIFY( c3 == ' ' );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-io.cc
new file mode 100644
index 000000000..306f93af7
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-io.cc
@@ -0,0 +1,87 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_03[] = "tmp_sgetc_1io.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sgetc()
+  // if read_cur not avail, return uflow(), else return *read_cur  
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; // in | out
+    fb_03.open(name_03, ios::out | ios::in | ios::trunc); 
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+    c1 = fb_03.sgetc();
+    c2 = fb_03.sbumpc();
+    VERIFY( c1 == traits_type::eof() );
+    VERIFY( c1 == c2 );
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+  }
+
+  // in | out 2
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.open(name_01, ios::in | ios::out);
+    VERIFY( !fb_01.write_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sgetc();
+    VERIFY( c1 == c2 );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sgetc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    VERIFY( c2 == ' ' );
+    VERIFY( c3 == ' ' );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-out.cc
new file mode 100644
index 000000000..32bc8092d
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/1-out.cc
@@ -0,0 +1,70 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sgetc_1out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sgetc()
+  // if read_cur not avail, return uflow(), else return *read_cur  
+
+  // out
+  {
+    constraint_filebuf fb_02; // out
+    fb_02.open(name_02, ios::out | ios::trunc);    
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+    c1 = fb_02.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_02.sgetc();
+    VERIFY( c2 == traits_type::eof() );
+    fb_02.sbumpc();
+    c1 = fb_02.sbumpc();
+    c2 = fb_02.sgetc();
+    VERIFY( c1 == c2 );
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-in.cc
new file mode 100644
index 000000000..d3c179786
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-in.cc
@@ -0,0 +1,72 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sgetc()
+  // if read_cur not avail, return uflow(), else return *read_cur  
+
+  // in
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::in);
+    VERIFY( fb_01.unbuffered() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sgetc();
+    VERIFY( c1 == c2 );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sgetc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    VERIFY( c2 == ' ' );
+    VERIFY( c3 == ' ' );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-io.cc
new file mode 100644
index 000000000..6f162c9f8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-io.cc
@@ -0,0 +1,86 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_03[] = "tmp_sgetc_2io.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sgetc()
+  // if read_cur not avail, return uflow(), else return *read_cur  
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; // in | out
+    fb_03.pubsetbuf(0, 0);
+    fb_03.open(name_03, ios::out | ios::in | ios::trunc); 
+    VERIFY( fb_03.unbuffered() );
+    c1 = fb_03.sgetc();
+    c2 = fb_03.sbumpc();
+    VERIFY( c1 == traits_type::eof() );
+    VERIFY( c1 == c2 );
+    VERIFY( fb_03.unbuffered() );
+  }
+
+  // in | out 2
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::in | ios::out);
+    VERIFY( fb_01.unbuffered() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sgetc();
+    VERIFY( c1 == c2 );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sgetc();
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == '/' );
+    VERIFY( c2 == ' ' );
+    VERIFY( c3 == ' ' );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-out.cc
new file mode 100644
index 000000000..04ea095dc
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetc/char/2-out.cc
@@ -0,0 +1,69 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sgetc_2out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sgetc()
+  // if read_cur not avail, return uflow(), else return *read_cur  
+
+  // out
+  {
+    constraint_filebuf fb_02; // out
+    fb_02.pubsetbuf(0, 0);
+    fb_02.open(name_02, ios::out | ios::trunc);    
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+    c1 = fb_02.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_02.sgetc();
+    VERIFY( c2 == traits_type::eof() );
+    fb_02.sbumpc();
+    c1 = fb_02.sbumpc();
+    c2 = fb_02.sgetc();
+    VERIFY( c1 == c2 );
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-in.cc
new file mode 100644
index 000000000..47c0597cb
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-in.cc
@@ -0,0 +1,92 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2006, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// The ARM simulator does not provide support for "fstat", which
+// causes "in_avail" to return an incorrect value.
+// { dg-do run { xfail arm*-*-elf arm*-*-eabi } }
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+// { dg-require-binary-io "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetn.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  streamsize 			strmsz_1, strmsz_2;
+  char carray1[13] = "";
+  char carray2[8192] = "";
+  char buffer[8192] = "";
+  int_type 			c1, c4;
+  
+  // streamsize sgetn(char_type *s, streamsize n)
+  // streamsize xsgetn(char_type *s, streamsize n)
+  // assign up to n chars to s from input sequence, indexing in_cur as
+  // approp and returning the number of chars assigned
+
+  // in 
+  {
+    constraint_filebuf fb_01;
+    // Need this since BUFSIZ is only guaranteed >= 255 and we want
+    // to trigger the same underflow situation everywhere.
+    fb_01.pubsetbuf(buffer, 8192);
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( !fb_01.write_position() );
+    strmsz_1 = fb_01.in_avail(); // 8261
+    strmsz_2 = fb_01.sgetn(carray1, 10);
+    VERIFY( strmsz_2 == 10 );
+    strmsz_2 = fb_01.in_avail(); 
+    VERIFY( strmsz_1 > strmsz_2 );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == 'b' );  
+    strmsz_1 = fb_01.in_avail();
+    strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
+    VERIFY( strmsz_1 == strmsz_2 - 5 ); 
+    c4 = fb_01.sgetc(); // buffer should have underflowed from above.
+    VERIFY( c4 == 'e' );
+    strmsz_1 = fb_01.in_avail();
+    VERIFY( strmsz_1 > 0 );
+    strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
+    VERIFY( strmsz_1 == strmsz_2 ); //at the end of the actual file 
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-io.cc
new file mode 100644
index 000000000..ffcdc2c14
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-io.cc
@@ -0,0 +1,105 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2006, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// The ARM simulator does not provide support for "fstat", which
+// causes "in_avail" to return an incorrect value.
+// { dg-do run { xfail arm*-*-elf arm*-*-eabi } }
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+// { dg-require-binary-io "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetn.txt"; // file with data in it
+const char name_03[] = "tmp_sgetn_1io.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  streamsize 			strmsz_1, strmsz_2;
+  char carray1[13] = "";
+  char carray2[8192] = "";
+  char buffer[8192] = "";
+  int_type 			c1, c4;
+  
+  // streamsize sgetn(char_type *s, streamsize n)
+  // streamsize xsgetn(char_type *s, streamsize n)
+  // assign up to n chars to s from input sequence, indexing in_cur as
+  // approp and returning the number of chars assigned
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; 
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc); 
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+    strmsz_1 = fb_03.sgetn(carray1, 10);
+    VERIFY( strmsz_1 == 0 ); 
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+  }
+
+  // in | out 2
+  {
+    constraint_filebuf fb_01;
+    // Need this since BUFSIZ is only guaranteed >= 255 and we want
+    // to trigger the same underflow situation everywhere.
+    fb_01.pubsetbuf(buffer, 8192);
+    fb_01.open(name_01, ios_base::in | ios_base::out);
+    VERIFY( !fb_01.write_position() );
+    strmsz_1 = fb_01.in_avail();
+    strmsz_2 = fb_01.sgetn(carray1, 10);
+    VERIFY( strmsz_2 == 10 );
+    strmsz_2 = fb_01.in_avail(); 
+    VERIFY( strmsz_1 > strmsz_2 );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == 'b' );  
+    strmsz_1 = fb_01.in_avail();
+    strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
+    VERIFY( strmsz_1 == strmsz_2 - 5 ); 
+    c4 = fb_01.sgetc(); // buffer should have underflowed from above.
+    VERIFY( c4 == 'e' );
+    strmsz_1 = fb_01.in_avail();
+    VERIFY( strmsz_1 > 0 );
+    strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
+    VERIFY( strmsz_1 == strmsz_2 ); //at the end of the actual file 
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-out.cc
new file mode 100644
index 000000000..c9da66539
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-out.cc
@@ -0,0 +1,76 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sgetn_1out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  streamsize 			strmsz_1, strmsz_2;
+  char carray2[8192] = "";
+  int_type 			c2, c4;
+  
+  // streamsize sgetn(char_type *s, streamsize n)
+  // streamsize xsgetn(char_type *s, streamsize n)
+  // assign up to n chars to s from input sequence, indexing in_cur as
+  // approp and returning the number of chars assigned
+
+  // out
+  {
+    constraint_filebuf fb_02;
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+    strmsz_2 = fb_02.in_avail();
+    strmsz_2 = fb_02.sgetn(carray2, 10);
+    VERIFY( strmsz_2 == 0 );
+    c2 = fb_02.sgetc();
+    VERIFY( c2 == traits_type::eof() );
+    strmsz_1 = fb_02.in_avail();
+    strmsz_2 = fb_02.sgetn(carray2, strmsz_1 + 5);
+    VERIFY( strmsz_1 == -1 );
+    VERIFY( strmsz_2 == 0 );
+    c4 = fb_02.sgetc(); 
+    VERIFY( c4 == traits_type::eof() );
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-in.cc
new file mode 100644
index 000000000..dda7c67e3
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-in.cc
@@ -0,0 +1,88 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2006, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// The ARM simulator does not provide support for "fstat", which
+// causes "in_avail" to return an incorrect value.
+// { dg-do run { xfail arm*-*-elf arm*-*-eabi } }
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+// { dg-require-binary-io "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetn.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  streamsize 			strmsz_1, strmsz_2;
+  char carray1[13] = "";
+  char carray2[8192] = "";
+  int_type 			c1, c4;
+  
+  // streamsize sgetn(char_type *s, streamsize n)
+  // streamsize xsgetn(char_type *s, streamsize n)
+  // assign up to n chars to s from input sequence, indexing in_cur as
+  // approp and returning the number of chars assigned
+
+  // in 
+  {
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( fb_01.unbuffered() );
+    strmsz_1 = fb_01.in_avail();
+    strmsz_2 = fb_01.sgetn(carray1, 10);
+    VERIFY( strmsz_2 == 10 );
+    strmsz_2 = fb_01.in_avail(); 
+    VERIFY( strmsz_1 > strmsz_2 );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == 'b' );  
+    strmsz_1 = fb_01.in_avail(); // 8181 or 8250 depending on buffer
+    strmsz_2 = fb_01.sgetn(carray2, 8181 + 5);
+    VERIFY( 8181 == strmsz_2 - 5 ); 
+    c4 = fb_01.sgetc(); // buffer should have underflowed from above.
+    VERIFY( c4 == 'e' );
+    strmsz_1 = fb_01.in_avail();
+    VERIFY( strmsz_1 > 0 );
+    strmsz_2 = fb_01.sgetn(carray2, 65 + 5);
+    VERIFY( 70 == strmsz_2 ); // at the end of the actual file 
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-io.cc
new file mode 100644
index 000000000..d401f8732
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-io.cc
@@ -0,0 +1,100 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2006, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// The ARM simulator does not provide support for "fstat", which
+// causes "in_avail" to return an incorrect value.
+// { dg-do run { xfail arm*-*-elf arm*-*-eabi } }
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+// { dg-require-binary-io "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetn.txt"; // file with data in it
+const char name_03[] = "tmp_sgetn_2io.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  streamsize 			strmsz_1, strmsz_2;
+  char carray1[13] = "";
+  char carray2[8192] = "";
+  int_type 			c1, c4;
+  
+  // streamsize sgetn(char_type *s, streamsize n)
+  // streamsize xsgetn(char_type *s, streamsize n)
+  // assign up to n chars to s from input sequence, indexing in_cur as
+  // approp and returning the number of chars assigned
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; 
+    fb_03.pubsetbuf(0, 0);
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc); 
+    VERIFY( fb_03.unbuffered() );
+    strmsz_1 = fb_03.sgetn(carray1, 10);
+    VERIFY( strmsz_1 == 0 ); 
+    VERIFY( fb_03.unbuffered() );
+  }
+
+  // in | out 2
+  {
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in | ios_base::out);
+    VERIFY( fb_01.unbuffered() );
+    strmsz_1 = fb_01.in_avail();
+    strmsz_2 = fb_01.sgetn(carray1, 10);
+    VERIFY( strmsz_2 == 10 );
+    strmsz_2 = fb_01.in_avail(); 
+    VERIFY( strmsz_1 > strmsz_2 );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == 'b' );  
+    strmsz_1 = fb_01.in_avail();
+    strmsz_2 = fb_01.sgetn(carray2, 8181 + 5);
+    VERIFY( 8181 == strmsz_2 - 5 ); 
+    c4 = fb_01.sgetc(); // buffer should have underflowed from above.
+    VERIFY( c4 == 'e' );
+    strmsz_1 = fb_01.in_avail();
+    VERIFY( strmsz_1 > 0 );
+    strmsz_2 = fb_01.sgetn(carray2, 65 + 5);
+    VERIFY( 70 == strmsz_2 ); //at the end of the actual file 
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-out.cc
new file mode 100644
index 000000000..fd332b683
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/2-out.cc
@@ -0,0 +1,76 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sgetn_2out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+
+  streamsize 			strmsz_1, strmsz_2;
+  char carray2[8192] = "";
+  int_type 			c2;
+  
+  // streamsize sgetn(char_type *s, streamsize n)
+  // streamsize xsgetn(char_type *s, streamsize n)
+  // assign up to n chars to s from input sequence, indexing in_cur as
+  // approp and returning the number of chars assigned
+
+  // out
+  {
+    constraint_filebuf fb_02; 
+    fb_02.pubsetbuf(0, 0);
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+    strmsz_2 = fb_02.in_avail();
+    strmsz_2 = fb_02.sgetn(carray2, 10);
+    VERIFY( strmsz_2 == 0 );
+    c2 = fb_02.sgetc();
+    VERIFY( c2 == traits_type::eof() );
+    strmsz_1 = fb_02.in_avail();
+    strmsz_2 = fb_02.sgetn(carray2, strmsz_1 + 5);
+    VERIFY( strmsz_1 == -1 );
+    VERIFY( strmsz_2 == 0 );
+    fb_02.sgetc(); 
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/3.cc
new file mode 100644
index 000000000..146a23ea7
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/3.cc
@@ -0,0 +1,47 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "sgetn.txt"; 
+
+void test06()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  char buffer[] = "xxxxxxxxxx";
+  typedef filebuf::int_type	int_type;
+  filebuf fbuf01;
+  fbuf01.open(name_01, ios_base::in);
+  int_type len1 = fbuf01.sgetn(buffer, sizeof(buffer));
+  VERIFY( len1 == sizeof(buffer) );
+  VERIFY( buffer[0] == '/' );
+}
+
+int main() 
+{
+  test06();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/showmanyc/char/9533-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/showmanyc/char/9533-1.cc
new file mode 100644
index 000000000..5aa31d78f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/showmanyc/char/9533-1.cc
@@ -0,0 +1,98 @@
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fstream>
+#include <cstdlib>
+#include <testsuite_hooks.h>
+
+// libstdc++/9533
+void test_01()
+{
+  using namespace std;
+  using namespace __gnu_test;
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_fifo1";
+
+  const int count = 10000;
+
+  signal(SIGPIPE, SIG_IGN);
+  unlink(name);
+  
+  if (0 != mkfifo(name, S_IRWXU))
+    {
+      VERIFY( false );
+    }
+  
+  int fval = fork();
+  if (fval == -1)
+    {
+      unlink(name);
+      VERIFY( false );
+    }
+  else if (fval == 0)
+    {
+      filebuf ofbuf;
+      ofbuf.open(name, ios_base::in|ios_base::out);
+      VERIFY( ofbuf.is_open() );
+      sleep(1);
+
+      for (int i = 0; i < count; ++i)
+	ofbuf.sputc(i % 100);
+
+      ofbuf.pubsync();
+      sleep(1);
+      ofbuf.close();
+      exit(0);
+    }
+
+  filebuf ifbuf;
+  ifbuf.open(name, ios_base::in);
+  VERIFY( ifbuf.is_open() );
+
+  for (int j = 0; j < count; ++j)
+    {
+      filebuf::int_type c1 = ifbuf.sbumpc();
+      VERIFY( c1 == j % 100 );
+    }
+
+  filebuf::int_type c6 = ifbuf.sbumpc();
+  VERIFY( c6 == filebuf::traits_type::eof() );
+
+  sleep(2);
+  ifbuf.close();
+
+  unlink(name);
+}
+
+int
+main() 
+{
+  test_01();
+  return 0;
+}
+
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/showmanyc/char/9533-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/showmanyc/char/9533-2.cc
new file mode 100644
index 000000000..0cba3a8f6
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/showmanyc/char/9533-2.cc
@@ -0,0 +1,58 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+// libstdc++/9533
+void test_02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;  
+  const char* name = "tmp_file1";
+  const char* strlit = "0123456789";
+  
+  filebuf fb;
+
+  int written = 0;
+  fb.open(name, ios_base::out | ios_base::trunc);	
+  for (int i = 0; i < BUFSIZ; ++i)
+    written += fb.sputn(strlit, 10);
+  fb.close();
+  
+  int read = 0;
+  int n = 0;
+  char buf[10];
+  fb.open(name, ios_base::in);
+  do
+    {
+      n = fb.sgetn(buf, sizeof(buf));
+      read += n;
+    }
+  while (n);
+
+  VERIFY( read == written );
+}
+
+int
+main()
+{
+  test_02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-in.cc
new file mode 100644
index 000000000..93a3771fc
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-in.cc
@@ -0,0 +1,85 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_02[] = "tmp_snextc_1out.tst"; // empty file, need to create
+const char name_03[] = "tmp_snextc_1io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1;
+
+  // int_type snextc()
+  // calls sbumpc and if sbumpc != eof, return sgetc
+  
+  // in
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( !fb_01.write_position() );
+    c1 = fb_01.snextc();
+    VERIFY( c1 == '/' );
+    c1 = fb_01.snextc();
+    VERIFY( c1 == ' ' );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+
+  // in
+  {  
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( !fb_01.write_position() );
+    int_type c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == ' ' );
+    c1 = fb_01.snextc();
+    VERIFY( c1 == '9' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == '9' );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-io.cc
new file mode 100644
index 000000000..7d51c0c98
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-io.cc
@@ -0,0 +1,84 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_02[] = "tmp_snextc_1out.tst"; // empty file, need to create
+const char name_03[] = "tmp_snextc_1io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c3;
+
+  // int_type snextc()
+  // calls sbumpc and if sbumpc != eof, return sgetc
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; 
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+    c3 = fb_03.snextc();
+    VERIFY( c3 == traits_type::eof() );
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+ }
+
+  // in | out 2
+  {  
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::in | ios_base::out);
+    VERIFY( !fb_01.write_position() );
+    int_type c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == ' ' );
+    c1 = fb_01.snextc();
+    VERIFY( c1 == '9' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == '9' );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-out.cc
new file mode 100644
index 000000000..e993fc7fe
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/1-out.cc
@@ -0,0 +1,65 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_02[] = "tmp_snextc_1out.tst"; // empty file, need to create
+const char name_03[] = "tmp_snextc_1io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c2;
+
+  // int_type snextc()
+  // calls sbumpc and if sbumpc != eof, return sgetc
+
+  // out
+  {    
+    constraint_filebuf fb_02;
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+    c2 = fb_02.snextc();
+    VERIFY( c2 == traits_type::eof() );
+    c2 = fb_02.snextc();
+    VERIFY( c2 == traits_type::eof() );
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-in.cc
new file mode 100644
index 000000000..77b40d4c4
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-in.cc
@@ -0,0 +1,83 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1;
+
+  // int_type snextc()
+  // calls sbumpc and if sbumpc != eof, return sgetc
+  
+  // in
+  {
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( fb_01.unbuffered() );
+    c1 = fb_01.snextc();
+    VERIFY( c1 == '/' ); // overflow
+    c1 = fb_01.snextc();
+    VERIFY( c1 == ' ' ); 
+    VERIFY( fb_01.unbuffered() );
+  }
+
+  // in
+  {  
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( fb_01.unbuffered() );
+    int_type c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == ' ' );
+    c1 = fb_01.snextc();
+    VERIFY( c1 == '9' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == '9' );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-io.cc
new file mode 100644
index 000000000..e0c6f71db
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-io.cc
@@ -0,0 +1,82 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+const char name_03[] = "tmp_snextc_2io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c3;
+
+  // int_type snextc()
+  // calls sbumpc and if sbumpc != eof, return sgetc
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; 
+    fb_03.pubsetbuf(0, 0);
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( fb_03.unbuffered() );
+    c3 = fb_03.snextc();
+    VERIFY( c3 == traits_type::eof() );
+    VERIFY( fb_03.unbuffered() );
+  }
+
+  // in | out 2
+  {  
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in | ios_base::out);
+    VERIFY( fb_01.unbuffered() );
+    int_type c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sbumpc();
+    VERIFY( c4 == '/' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == ' ' );
+    c1 = fb_01.snextc();
+    VERIFY( c1 == '9' );
+    c4 = fb_01.sgetc();
+    VERIFY( c4 == '9' );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-out.cc
new file mode 100644
index 000000000..728b2867e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/snextc/char/2-out.cc
@@ -0,0 +1,62 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_snextc_2out.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c2;
+
+  // int_type snextc()
+  // calls sbumpc and if sbumpc != eof, return sgetc
+
+  // out
+  {    
+    constraint_filebuf fb_02;
+    fb_02.pubsetbuf(0, 0);
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( fb_02.unbuffered() );
+    c2 = fb_02.snextc();
+    VERIFY( c2 == traits_type::eof() );
+    c2 = fb_02.snextc();
+    VERIFY( c2 == traits_type::eof() );
+    VERIFY( fb_02.unbuffered() );
+ }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-in.cc
new file mode 100644
index 000000000..f8190a9cd
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-in.cc
@@ -0,0 +1,93 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.open(name_01, ios::in);
+    VERIFY( !fb_01.write_position() );
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sputbackc('/');
+    VERIFY( c1 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == ' ' );
+    c1 = fb_01.sgetc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == 'a' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == c3 );
+    fb_01.pubseekoff(5, ios_base::beg, ios_base::in);
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '0' );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '1' );
+    c2 = fb_01.sputbackc('b');
+    VERIFY( c2 == 'b' );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '1' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '7' );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-io.cc
new file mode 100644
index 000000000..726947379
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-io.cc
@@ -0,0 +1,103 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_1io.tst"; // empty file, need to create
+
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in | out
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+    strmsz_1 = fb_01.sputn("racadabras", 10);//"abracadabras or what?"
+    strmsz_2 = fb_01.sputn(", i wanna reach out and", 10);
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    c1 = fb_01.sgetc(); // -1
+    c2 = fb_01.sputbackc('z');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( 1 == strmsz_2 );
+    //test for _in_cur == _in_beg
+    // fb_01._M_out_beg = "bd23456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZracada" etc
+    fb_01.pubseekoff(10, std::ios_base::beg);
+    fb_01.sputc('m');
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    strmsz_1 = fb_01.in_avail(); 
+    c1 = fb_01.sgetc(); 
+    fb_01.snextc();
+    c2 = fb_01.sputbackc('z');  
+    strmsz_2 = fb_01.in_avail(); 
+    c3 = fb_01.sgetc();  
+    VERIFY( c1 != c2 );
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( c2 == 'z' );
+    // test for replacing char with identical one
+    fb_01.snextc();
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    fb_01.sputc('u');
+    fb_01.sputc('v');
+    fb_01.sputc('a');
+    fb_01.pubseekoff(0, std::ios_base::end);
+    strmsz_1 = fb_01.in_avail();
+    c2 = fb_01.sputbackc('a');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( strmsz_1 + 1 == strmsz_2 );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-out.cc
new file mode 100644
index 000000000..2cd1fdfef
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/1-out.cc
@@ -0,0 +1,71 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_1out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // out
+  {
+    constraint_filebuf fb_01; // out
+    fb_01.open(name_01, ios::out | ios::trunc);    
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == traits_type::eof() );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c1 == c2 );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-in.cc
new file mode 100644
index 000000000..a2aa792e8
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-in.cc
@@ -0,0 +1,93 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in
+  {
+    constraint_filebuf fb_01; // in 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::in);
+    VERIFY( fb_01.unbuffered() );
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sputbackc('/');
+    VERIFY( c1 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == ' ' );
+    c1 = fb_01.sgetc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == 'a' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == c2 );
+    c3 = fb_01.sgetc();
+    VERIFY( c1 == c3 );
+    fb_01.pubseekoff(5, ios_base::beg, ios_base::in);
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == '0' );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '1' );
+    c2 = fb_01.sputbackc('b');
+    VERIFY( c2 == 'b' );
+    fb_01.sbumpc();
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '1' );
+    c3 = fb_01.sbumpc();
+    VERIFY( c3 == '7' );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-io.cc
new file mode 100644
index 000000000..588c6b9b7
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-io.cc
@@ -0,0 +1,102 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_2io.tst"; // empty file, need to create
+
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+  int_type 			c1, c2, c3;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // in | out
+  {
+    constraint_filebuf fb_01;
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( fb_01.unbuffered() );
+    strmsz_1 = fb_01.sputn("racadabras", 10);//"abracadabras or what?"
+    strmsz_2 = fb_01.sputn(", i wanna reach out and", 10);
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    c1 = fb_01.sgetc(); // -1
+    c2 = fb_01.sputbackc('z');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( 1 == strmsz_2 );
+    //test for _in_cur == _in_beg
+    // fb_01._M_out_beg = "bd23456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZracada" etc
+    fb_01.pubseekoff(10, std::ios_base::beg);
+    fb_01.sputc('m');
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    strmsz_1 = fb_01.in_avail(); 
+    c1 = fb_01.sgetc(); 
+    fb_01.snextc();
+    c2 = fb_01.sputbackc('z');  
+    strmsz_2 = fb_01.in_avail(); 
+    c3 = fb_01.sgetc();  
+    VERIFY( c1 != c2 );
+    VERIFY( c3 == c2 );
+    VERIFY( c1 != c3 );
+    VERIFY( c2 == 'z' );
+    // test for replacing char with identical one
+    fb_01.snextc();
+    fb_01.pubseekoff(0, std::ios_base::cur);
+    fb_01.sputc('u');
+    fb_01.sputc('v');
+    fb_01.sputc('a');
+    fb_01.pubseekoff(0, std::ios_base::end);
+    strmsz_1 = fb_01.in_avail();
+    c2 = fb_01.sputbackc('a');
+    strmsz_2 = fb_01.in_avail();
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    VERIFY( strmsz_1 + 1 == strmsz_2 );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-out.cc
new file mode 100644
index 000000000..f72ef3b67
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/2-out.cc
@@ -0,0 +1,72 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sputbackc_2out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputbackc(char_type c)
+  // if in_cur not avail || ! traits::eq(c, gptr() [-1]), return pbfail
+  // otherwise decrements in_cur and returns *gptr()
+
+  // out
+  {
+    constraint_filebuf fb_01; // out
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::out | ios::trunc);    
+    VERIFY( fb_01.unbuffered() );
+    VERIFY( !fb_01.read_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c2 == traits_type::eof() );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sputbackc('a');
+    VERIFY( c1 == c2 );
+    VERIFY( fb_01.unbuffered() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/9425.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/9425.cc
new file mode 100644
index 000000000..608f13260
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputbackc/char/9425.cc
@@ -0,0 +1,49 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+// libstdc++/9439, libstdc++/9425
+// basic_filebuf<>::pbackfail calls basic_filebuf<>::seekoff, but
+// fails to check the return value
+void test09()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbuf;
+  fbuf.open(name_01, ios_base::in);
+  filebuf::int_type r = fbuf.sputbackc('a');
+  fbuf.close();
+
+  VERIFY( r == filebuf::traits_type::eof() );
+}
+
+int main() 
+{
+  test09();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-in.cc
new file mode 100644
index 000000000..53d8734e3
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-in.cc
@@ -0,0 +1,62 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c3;
+
+  // int_type sputc(char_type c)
+  // if out_cur not avail, return overflow(traits_type::to_int_type(c)) 
+  // else, stores c at out_cur,
+  // increments out_cur, and returns c as int_type
+
+  // in 
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( !fb_01.write_position() );
+    c3 = fb_01.sputc('a'); 
+    VERIFY( c3 == traits_type::eof() );
+    VERIFY( !fb_01.write_position() );
+   }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-io.cc
new file mode 100644
index 000000000..f0e446c70
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-io.cc
@@ -0,0 +1,71 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_03[] = "tmp_sputc_1io.tst";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputc(char_type c)
+  // if out_cur not avail, return overflow(traits_type::to_int_type(c)) 
+  // else, stores c at out_cur,
+  // increments out_cur, and returns c as int_type
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; 
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+    c1 = fb_03.sputc('b'); 
+    VERIFY( c1 == 'b' );
+    c2 = fb_03.sputc('d'); 
+    VERIFY( c2 == 'd' );
+    for (int i = 50; i <= 90; ++i) 
+      c2 = fb_03.sputc(char(i));
+    VERIFY( fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-out.cc
new file mode 100644
index 000000000..1c7ee8237
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1-out.cc
@@ -0,0 +1,70 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sputc_1out.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputc(char_type c)
+  // if out_cur not avail, return overflow(traits_type::to_int_type(c)) 
+  // else, stores c at out_cur,
+  // increments out_cur, and returns c as int_type
+
+  // out
+  {
+    constraint_filebuf fb_02; 
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+    c1 = fb_02.sputc('a');
+    VERIFY( c1 == 'a' ); 
+    c2 = fb_02.sputc('c'); 
+    VERIFY( c2 == 'c' );
+    for (int i = 50; i <= 90; ++i) 
+      c2 = fb_02.sputc(char(i));
+    VERIFY( fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1057.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1057.cc
new file mode 100644
index 000000000..a2368f932
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/1057.cc
@@ -0,0 +1,53 @@
+// 1999-10-11 bkoz
+
+// Copyright (C) 1999, 2000, 2001, 2002, 2003, 2009, 2010
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+
+// 27.5.2 template class basic_streambuf
+
+#include <string>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class nullsetpbuf : public std::filebuf
+{
+  char foo[64];
+public:
+  nullsetpbuf()
+  {
+    setp(foo, foo + 64);
+    setp(0, 0);
+  }
+};
+
+// libstdc++/1057
+void test05()
+{
+  std::string text1 = "abcdefghijklmn";
+  
+  nullsetpbuf nsp;
+  // Immediate crash as sputc writes to null pointer
+  nsp.sputc('a');
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-in.cc
new file mode 100644
index 000000000..e6a7f069f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-in.cc
@@ -0,0 +1,63 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c3;
+
+  // int_type sputc(char_type c)
+  // if out_cur not avail, return overflow(traits_type::to_int_type(c)) 
+  // else, stores c at out_cur,
+  // increments out_cur, and returns c as int_type
+
+  // in 
+  {
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( fb_01.unbuffered() );
+    c3 = fb_01.sputc('a'); 
+    VERIFY( c3 == traits_type::eof() );
+    VERIFY( fb_01.unbuffered() );
+   }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-io.cc
new file mode 100644
index 000000000..16645f8db
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-io.cc
@@ -0,0 +1,70 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_03[] = "tmp_sputc_2io.tst";
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputc(char_type c)
+  // if out_cur not avail, return overflow(traits_type::to_int_type(c)) 
+  // else, stores c at out_cur,
+  // increments out_cur, and returns c as int_type
+
+  // in | out 1
+  {
+    constraint_filebuf fb_03; 
+    fb_03.pubsetbuf(0, 0);
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( fb_03.unbuffered() );
+    c1 = fb_03.sputc('b'); 
+    VERIFY( c1 == 'b' );
+    c2 = fb_03.sputc('d'); 
+    VERIFY( c2 == 'd' );
+    for (int i = 50; i <= 90; ++i) 
+      c2 = fb_03.sputc(char(i));
+    VERIFY( fb_03.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-out.cc
new file mode 100644
index 000000000..9572be161
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/2-out.cc
@@ -0,0 +1,71 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sputc_2out.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sputc(char_type c)
+  // if out_cur not avail, return overflow(traits_type::to_int_type(c)) 
+  // else, stores c at out_cur,
+  // increments out_cur, and returns c as int_type
+
+  // out
+  {
+    constraint_filebuf fb_02; 
+    fb_02.pubsetbuf(0, 0);
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+    c1 = fb_02.sputc('a');
+    VERIFY( c1 == 'a' ); 
+    c2 = fb_02.sputc('c'); 
+    VERIFY( c2 == 'c' );
+    for (int i = 50; i <= 90; ++i) 
+      c2 = fb_02.sputc(char(i));
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/9701-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/9701-2.cc
new file mode 100644
index 000000000..1fdf45955
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputc/char/9701-2.cc
@@ -0,0 +1,70 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_05[] = "filebuf_virtuals-5.txt"; // empty file, need to create
+
+bool over_called;
+
+class Derived_filebuf : public std::filebuf
+{
+public:
+  int_type overflow(int_type c)
+  {
+    over_called = true;
+    return std::filebuf::overflow(c);
+  }
+  
+  const char_type* pub_epptr() const
+  { return epptr(); }
+  
+  const char_type* pub_pptr() const
+  { return pptr(); }
+};
+
+// libstdc++/9701 (partial)
+void test11()
+{
+  bool test __attribute__((unused)) = true;
+
+  bool over_expected;
+
+  // sputc
+  Derived_filebuf dfbuf_01;
+  dfbuf_01.open(name_05, std::ios_base::out);
+  over_called = false;
+  dfbuf_01.sputc('i');
+  VERIFY( over_called );
+  over_expected = dfbuf_01.pub_epptr() == dfbuf_01.pub_pptr();
+  over_called = false;
+  dfbuf_01.sputc('v');
+  VERIFY( (!over_expected && !over_called)
+	  || (over_expected && over_called) );
+  dfbuf_01.close();
+}
+
+int main() 
+{
+  test11();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-in.cc
new file mode 100644
index 000000000..537ebe2ca
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-in.cc
@@ -0,0 +1,62 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  // streamsize sputn(const char_typs* s, streamsize n)
+  // write up to n chars to out_cur from s, returning number assigned
+  // NB *sputn will happily put '\0' into your stream if you give it a chance*
+
+  // in 
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( !fb_01.write_position() );
+    strmsz_1 = fb_01.sputn("racadabra", 10);
+    VERIFY( strmsz_1 == 0 );  
+    VERIFY( !fb_01.write_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-io.cc
new file mode 100644
index 000000000..39f4fed71
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-io.cc
@@ -0,0 +1,70 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_03[] = "tmp_sputn_1io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+
+  // streamsize sputn(const char_typs* s, streamsize n)
+  // write up to n chars to out_cur from s, returning number assigned
+  // NB *sputn will happily put '\0' into your stream if you give it a chance*
+
+  // in | out
+  {
+    constraint_filebuf fb_03; 
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( !fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+    strmsz_1 = fb_03.sputn("racadabras", 10);//"abracadabras or what?"
+    VERIFY( strmsz_1 == 10 );
+    strmsz_2 = fb_03.sputn(", i wanna reach out and", 10);
+    VERIFY( strmsz_2 == 10 );
+    VERIFY( strmsz_1 == strmsz_2 ); 
+    VERIFY( fb_03.write_position() );
+    VERIFY( !fb_03.read_position() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-out.cc
new file mode 100644
index 000000000..7abd18be1
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1-out.cc
@@ -0,0 +1,66 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sputn_1out.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  // streamsize sputn(const char_typs* s, streamsize n)
+  // write up to n chars to out_cur from s, returning number assigned
+  // NB *sputn will happily put '\0' into your stream if you give it a chance*
+
+  // out
+  {
+    constraint_filebuf fb_02; 
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( !fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+    strmsz_1 = fb_02.sputn("racadabras", 10);
+    VERIFY( strmsz_1 == 10 );  
+    VERIFY( fb_02.write_position() );
+    VERIFY( !fb_02.read_position() );
+   }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1057.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1057.cc
new file mode 100644
index 000000000..c84a079d2
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/1057.cc
@@ -0,0 +1,53 @@
+// 1999-10-11 bkoz
+
+// Copyright (C) 1999, 2000, 2001, 2002, 2003, 2009, 2010
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+
+// 27.5.2 template class basic_streambuf
+
+#include <string>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class nullsetpbuf : public std::filebuf
+{
+  char foo[64];
+public:
+  nullsetpbuf()
+  {
+    setp(foo, foo + 64);
+    setp(0, 0);
+  }
+};
+
+// libstdc++/1057
+void test05()
+{
+  std::string text1 = "abcdefghijklmn";
+  
+  nullsetpbuf nsp;
+  // Immediate crash as xsputn writes to null pointer
+  nsp.sputn(text1.c_str(), text1.length());
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-in.cc
new file mode 100644
index 000000000..7c2a92151
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-in.cc
@@ -0,0 +1,63 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  // streamsize sputn(const char_typs* s, streamsize n)
+  // write up to n chars to out_cur from s, returning number assigned
+  // NB *sputn will happily put '\0' into your stream if you give it a chance*
+
+  // in 
+  {
+    constraint_filebuf fb_01; 
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::in);
+    VERIFY( fb_01.unbuffered() );
+    strmsz_1 = fb_01.sputn("racadabra", 10);
+    VERIFY( strmsz_1 == 0 );  
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-io.cc
new file mode 100644
index 000000000..d5a5fdae1
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-io.cc
@@ -0,0 +1,69 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "filebuf_virtuals-1.txt"; // file with data in it
+const char name_03[] = "tmp_sputn_2io.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+
+  // streamsize sputn(const char_typs* s, streamsize n)
+  // write up to n chars to out_cur from s, returning number assigned
+  // NB *sputn will happily put '\0' into your stream if you give it a chance*
+
+  // in | out
+  {
+    constraint_filebuf fb_03; 
+    fb_03.pubsetbuf(0, 0);
+    fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( fb_03.unbuffered() );
+    strmsz_1 = fb_03.sputn("racadabras", 10);//"abracadabras or what?"
+    VERIFY( strmsz_1 == 10 );
+    strmsz_2 = fb_03.sputn(", i wanna reach out and", 10);
+    VERIFY( strmsz_2 == 10 );
+    VERIFY( strmsz_1 == strmsz_2 ); 
+    VERIFY( fb_03.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-out.cc
new file mode 100644
index 000000000..ab70def6c
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/2-out.cc
@@ -0,0 +1,67 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_02[] = "tmp_sputn_2out.tst"; // empty file, need to create
+
+void test05() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 			size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1;
+
+  // streamsize sputn(const char_typs* s, streamsize n)
+  // write up to n chars to out_cur from s, returning number assigned
+  // NB *sputn will happily put '\0' into your stream if you give it a chance*
+
+  // out
+  {
+    constraint_filebuf fb_02; 
+    fb_02.pubsetbuf(0, 0);
+    fb_02.open(name_02, ios_base::out | ios_base::trunc);
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+    strmsz_1 = fb_02.sputn("racadabras", 10);
+    VERIFY( strmsz_1 == 10 );  
+    VERIFY( fb_02.unbuffered() );
+    VERIFY( !fb_02.read_position() );
+   }
+}
+
+int main() 
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/9339.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/9339.cc
new file mode 100644
index 000000000..154fdba9a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/9339.cc
@@ -0,0 +1,49 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+// libstdc++/9339
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbuf01;
+  int len = 35;
+  fbuf01.pubsetbuf(0, 0);
+  fbuf01.open("tmp_9339", ios_base::out | ios_base::trunc);
+  streamsize s1 = fbuf01.sputn("Pete Goldlust @ Carl Hammer Gallery", len);
+  VERIFY( s1 == len );
+  fbuf01.close();
+
+  filebuf fbuf02;
+  char buf[256];
+  fbuf02.open("tmp_9339", ios_base::in);
+  streamsize s2 = fbuf02.sgetn(buf, 256);
+  VERIFY( s2 == len );
+  fbuf02.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/9701-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/9701-1.cc
new file mode 100644
index 000000000..1379fe004
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sputn/char/9701-1.cc
@@ -0,0 +1,74 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_05[] = "filebuf_virtuals-5.txt"; // empty file, need to create
+
+bool over_called;
+
+class Derived_filebuf : public std::filebuf
+{
+public:
+  int_type overflow(int_type c)
+  {
+    over_called = true;
+    return std::filebuf::overflow(c);
+  }
+  
+  const char_type* pub_epptr() const
+  {
+    return epptr();
+  }
+  
+  const char_type* pub_pptr() const
+  {
+    return pptr();
+  }
+};
+
+// libstdc++/9701 (partial)
+void test11()
+{
+  bool test __attribute__((unused)) = true;
+
+  bool over_expected;
+
+  // sputn
+  Derived_filebuf dfbuf_02;
+  dfbuf_02.open(name_05, std::ios_base::out);
+  over_called = false;
+  dfbuf_02.sputn("sonne's", 7);
+  VERIFY( over_called );
+  over_expected = dfbuf_02.pub_epptr() == dfbuf_02.pub_pptr();
+  over_called = false;
+  dfbuf_02.sputn(" peak", 5);
+  VERIFY( (!over_expected && !over_called)
+	  || (over_expected && over_called) );
+  dfbuf_02.close();
+}
+
+int main() 
+{
+  test11();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-in.cc
new file mode 100644
index 000000000..e4e17733b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-in.cc
@@ -0,0 +1,72 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			        c1, c2, c3;
+
+  // int_type sungetc()
+  // if in_cur not avail, return pbackfail(), else decrement and
+  // return to_int_type(*gptr())
+
+  // in
+  {
+    constraint_filebuf fb_01;
+    fb_01.open(name_01, ios::in);
+    VERIFY( !fb_01.write_position() );
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sungetc();
+    VERIFY( c2 == c1 );
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    fb_01.pubseekoff(2, ios_base::beg, ios_base::in);
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == ' ' );
+    c2 = fb_01.sungetc();
+    VERIFY( c2 == traits_type::not_eof(traits_type::eof()) );
+    VERIFY( !fb_01.write_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-io.cc
new file mode 100644
index 000000000..54a1372b4
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-io.cc
@@ -0,0 +1,84 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sungetc_1io.tst"; // empty file, need to create
+
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 		size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+  int_type 			c1, c2;
+
+  // int_type sungetc()
+  // if in_cur not avail, return pbackfail(), else decrement and
+  // return to_int_type(*gptr())
+
+  // in | out
+  {
+    constraint_filebuf fb_01; 
+    fb_01.open(name_01, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+    fb_01.sputc('u');
+    fb_01.sputc('v');
+    fb_01.pubseekoff(-1, std::ios_base::end);
+    fb_01.sbumpc();
+    strmsz_1 = fb_01.in_avail();
+    c2 = fb_01.sungetc(); 
+    strmsz_2 = fb_01.in_avail();
+    VERIFY( c2 == 'v' ); //  VERIFY( c2 != traits_type::eof() );
+    VERIFY( strmsz_1 + 1 == strmsz_2 );
+    //test for _in_cur == _in_end
+    fb_01.pubseekoff(0, std::ios_base::end);
+    strmsz_1 = fb_01.in_avail(); // -1 cuz at the end
+    c1 = fb_01.sgetc(); 
+    c2 = fb_01.sungetc();
+    strmsz_2 = fb_01.in_avail(); // 1
+    fb_01.sgetc();
+    VERIFY( c1 != c2 );
+    VERIFY( strmsz_2 != strmsz_1 );
+    VERIFY( strmsz_2 == 1 );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-out.cc
new file mode 100644
index 000000000..759cb0039
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/1-out.cc
@@ -0,0 +1,69 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sungetc_1out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sungetc()
+  // if in_cur not avail, return pbackfail(), else decrement and
+  // return to_int_type(*gptr())
+
+  // out
+  {
+    constraint_filebuf fb_01; // out
+    fb_01.open(name_01, ios::out | ios::trunc);    
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_01.sungetc();
+    VERIFY( c2 == traits_type::eof() );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sungetc();
+    VERIFY( c1 == c2 );
+    VERIFY( !fb_01.write_position() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-in.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-in.cc
new file mode 100644
index 000000000..94e176a6a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-in.cc
@@ -0,0 +1,73 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "sgetc.txt"; // file with data in it
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			        c1, c2, c3;
+
+  // int_type sungetc()
+  // if in_cur not avail, return pbackfail(), else decrement and
+  // return to_int_type(*gptr())
+
+  // in
+  {
+    constraint_filebuf fb_01;
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::in);
+    VERIFY( fb_01.unbuffered() );
+    c1 = fb_01.sbumpc();
+    VERIFY( c1 == '/' );
+    c2 = fb_01.sungetc();
+    VERIFY( c2 == c1 );
+    c3 = fb_01.sgetc();
+    VERIFY( c3 == c2 );
+    fb_01.pubseekoff(2, ios_base::beg, ios_base::in);
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == ' ' );
+    c2 = fb_01.sungetc();
+    VERIFY( c2 == traits_type::not_eof(traits_type::eof()) );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-io.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-io.cc
new file mode 100644
index 000000000..782a83db9
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-io.cc
@@ -0,0 +1,83 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009, 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sungetc_2io.tst"; // empty file, need to create
+
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+
+  typedef filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 	traits_type;
+  typedef size_t 		size_type;
+
+  bool test __attribute__((unused)) = true;
+  streamsize 			strmsz_1, strmsz_2;
+  int_type 			c1, c2;
+
+  // int_type sungetc()
+  // if in_cur not avail, return pbackfail(), else decrement and
+  // return to_int_type(*gptr())
+
+  // in | out
+  {
+    constraint_filebuf fb_01;
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios_base::out | ios_base::in | ios_base::trunc);
+    VERIFY( fb_01.unbuffered() );
+    fb_01.sputc('u');
+    fb_01.sputc('v');
+    fb_01.pubseekoff(-1, std::ios_base::end);
+    fb_01.sbumpc();
+    strmsz_1 = fb_01.in_avail();
+    c2 = fb_01.sungetc(); 
+    strmsz_2 = fb_01.in_avail();
+    VERIFY( c2 == 'v' ); //  VERIFY( c2 != traits_type::eof() );
+    VERIFY( strmsz_1 + 1 == strmsz_2 );
+    //test for _in_cur == _in_end
+    fb_01.pubseekoff(0, std::ios_base::end);
+    strmsz_1 = fb_01.in_avail(); // -1 cuz at the end
+    c1 = fb_01.sgetc(); 
+    c2 = fb_01.sungetc();
+    strmsz_2 = fb_01.in_avail(); // 1
+    fb_01.sgetc();
+    VERIFY( c1 != c2 );
+    VERIFY( strmsz_2 != strmsz_1 );
+    VERIFY( strmsz_2 == 1 );
+    VERIFY( fb_01.unbuffered() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-out.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-out.cc
new file mode 100644
index 000000000..dbdd9ab45
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sungetc/char/2-out.cc
@@ -0,0 +1,70 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+#include <testsuite_io.h>
+
+// @require@ %-*.tst %-*.txt
+// @diff@ %-*.tst %*.txt
+
+const char name_01[] = "tmp_sungetc_2out.tst"; // empty file, need to create
+
+// Test overloaded virtual functions.
+void test01() 
+{
+  using namespace std;
+  using namespace __gnu_test;
+  typedef std::filebuf::int_type 	int_type;
+  typedef filebuf::traits_type 		traits_type;
+
+  bool test __attribute__((unused)) = true;
+  int_type 			c1, c2;
+
+  // int_type sungetc()
+  // if in_cur not avail, return pbackfail(), else decrement and
+  // return to_int_type(*gptr())
+
+  // out
+  {
+    constraint_filebuf fb_01; // out
+    fb_01.pubsetbuf(0, 0);
+    fb_01.open(name_01, ios::out | ios::trunc);    
+    VERIFY( fb_01.unbuffered() );
+    VERIFY( !fb_01.read_position() );
+    c1 = fb_01.sgetc();
+    VERIFY( c1 == traits_type::eof() );
+    c2 = fb_01.sungetc();
+    VERIFY( c2 == traits_type::eof() );
+    fb_01.sbumpc();
+    c1 = fb_01.sbumpc();
+    c2 = fb_01.sungetc();
+    VERIFY( c1 == c2 );
+    VERIFY( fb_01.unbuffered() );
+    VERIFY( !fb_01.read_position() );
+  }
+}
+
+int main() 
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sync/char/1057.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sync/char/1057.cc
new file mode 100644
index 000000000..832e29558
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sync/char/1057.cc
@@ -0,0 +1,104 @@
+// 1999-10-11 bkoz
+
+// Copyright (C) 1999, 2000, 2001, 2002, 2003, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+
+// 27.5.2 template class basic_streambuf
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+class setpbuf : public std::filebuf
+{
+  char 		buffer[4];
+  std::string 	result;
+
+public:
+
+  std::string&
+  get_result()
+  { return result; }
+
+  setpbuf()
+  {
+    this->open("tmp_1057", std::ios_base::out | std::ios_base::trunc);
+    char foo [32];
+    setp(foo, foo + 32);
+    setp(buffer, buffer + 4);
+  }
+
+  ~setpbuf()
+  { 
+    sync(); 
+    close();
+  }
+
+  virtual int_type 
+  overflow(int_type n)
+  {
+    if (sync() != 0)
+      return traits_type::eof();
+    
+    result += traits_type::to_char_type(n);
+    
+    return n;
+  }
+  
+  virtual int 
+  sync()
+  {
+    result.append(pbase(), pptr());
+    setp(buffer, buffer + 4);
+    return 0;
+  }
+};
+
+// libstdc++/1057
+void test04()
+{
+  bool test __attribute__((unused)) = true;
+  std::string text = "abcdefghijklmn";
+  
+  // 01
+  setpbuf sp1;
+  // Here xsputn writes over sp1.result
+  sp1.sputn(text.c_str(), text.length());
+
+  // This crashes when result is accessed
+  sp1.pubsync();
+  VERIFY( sp1.get_result() == text );
+  
+  // 02
+  setpbuf sp2;
+  for (std::string::size_type i = 0; i < text.length(); ++i)
+    {
+      // sputc also writes over result
+      sp2.sputc(text[i]);
+    }
+  
+  // Crash here
+  sp2.pubsync();
+  VERIFY( sp2.get_result() == text );
+}
+
+int main() 
+{
+  test04();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/sync/char/9182-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/sync/char/9182-1.cc
new file mode 100644
index 000000000..a2a262a0d
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/sync/char/9182-1.cc
@@ -0,0 +1,79 @@
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+const char name_07[] = "filebuf_virtuals-7.txt"; // empty file, need to create
+
+class errorcvt : public std::codecvt<char, char, mbstate_t>
+{
+protected:
+  std::codecvt_base::result
+  do_out(mbstate_t&, const char* from, const char*,
+	 const char*& from_next, char* to, char*,
+	 char*& to_next) const
+  {
+    from_next = from;
+    to_next = to;
+    return std::codecvt<char, char, mbstate_t>::error;
+  }
+  
+  virtual bool do_always_noconv() const throw()
+  {
+    return false;
+  }
+};
+
+// libstdc++/9182
+// basic_filebuf<>::sync and overflow do not write out any characters
+// if codecvt<>::out returns error
+void test13()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc =  locale::classic();
+  loc = locale(loc, new errorcvt);
+  
+  filebuf fbuf1;
+  fbuf1.pubimbue(loc);
+  fbuf1.open(name_07, ios_base::out | ios_base::trunc);
+
+  try
+    {  
+      fbuf1.sputn("ison", 4); 
+      fbuf1.pubsync();
+      VERIFY( false );
+    }
+  catch (std::exception&)
+    {
+    }
+}
+
+int main() 
+{
+  test13();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/10096.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/10096.cc
new file mode 100644
index 000000000..fb8d2f615
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/10096.cc
@@ -0,0 +1,71 @@
+// 2003-05-03  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <string>
+#include <testsuite_hooks.h>
+
+class MyTraits : public std::char_traits<char>
+{
+};
+
+// libstdc++/10096
+void test01()
+{
+  using namespace std;
+
+  const char* name = "filebuf_virtuals-1.txt";
+
+  string str;
+  filebuf fb1;
+  fb1.open(name, ios_base::in);
+  
+  filebuf::int_type c1;
+  while ((c1 = fb1.sbumpc()) != filebuf::traits_type::eof())
+    str.push_back(filebuf::traits_type::to_char_type(c1));
+  fb1.close();
+
+  basic_filebuf<char, MyTraits> fb;
+  VERIFY( fb.sgetc() == MyTraits::eof() );
+
+  fb.open(name, ios_base::in);
+  VERIFY( fb.is_open() );
+
+  for (string::iterator i = str.begin(); i != str.end(); ++i)
+    {
+      MyTraits::int_type c2 = fb.sbumpc();
+      VERIFY( c2 != MyTraits::eof() );
+      VERIFY( c2 == MyTraits::to_int_type(*i) );
+    }
+
+  VERIFY( fb.sgetc() == MyTraits::eof() );
+  fb.close();
+  VERIFY( !fb.is_open() );
+  VERIFY( fb.sgetc() == MyTraits::eof() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/1.cc
new file mode 100644
index 000000000..03fcd7d9c
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/1.cc
@@ -0,0 +1,83 @@
+// 2003-05-03  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <string>
+#include <testsuite_hooks.h>
+
+// Check that basic_filebuf::underflow() handles
+// codecvt::always_noconv() == false and codecvt::in() == noconv.
+class NoconvCvt : public std::codecvt<char, char, std::mbstate_t>
+{
+protected:
+  virtual bool
+  do_always_noconv() const throw()
+  { return false; }
+
+  virtual result
+  do_in(state_type&, const char* from, const char*, const char*& from_next,
+	char* to, char*, char*& to_next)
+  {
+    from_next = from;
+    to_next = to;
+    return noconv;
+  }
+};
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char* name = "filebuf_virtuals-1.txt";
+
+  string str;
+  filebuf fb;
+  filebuf::int_type c1;
+
+  if (fb.open(name, ios_base::in))
+    {  
+      while ((c1 = fb.sbumpc()) != EOF)
+	str.push_back(filebuf::traits_type::to_char_type(c1));
+      fb.close();
+    }
+
+  locale loc(locale::classic(), new NoconvCvt);
+  fb.pubimbue(loc);
+
+  if (fb.open(name, ios_base::in))
+    {
+      for (string::iterator i = str.begin(); i != str.end(); ++i)
+	{
+	  c1 = fb.sbumpc();
+	  VERIFY( c1 != filebuf::traits_type::eof() );
+	  VERIFY( c1 == filebuf::traits_type::to_int_type(*i) );
+	}
+      VERIFY( fb.sgetc() == filebuf::traits_type::eof() );
+      fb.close();
+    }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/10097.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/10097.cc
new file mode 100644
index 000000000..af0e9141c
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/10097.cc
@@ -0,0 +1,115 @@
+// { dg-require-fork "" }
+// { dg-require-mkfifo "" }
+
+// 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
+
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <cstdlib>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+// No asserts, avoid leaking the semaphores if a VERIFY fails.
+#undef _GLIBCXX_ASSERT
+
+#include <testsuite_hooks.h>
+
+class UnderBuf : public std::filebuf
+{
+public:
+  int_type
+  pub_underflow()
+  { return underflow(); }
+
+  std::streamsize
+  pub_showmanyc()
+  { return showmanyc(); }
+};
+
+// libstdc++/10097
+// filebuf::underflow drops characters.
+bool test16()
+{
+  using namespace std;
+  using namespace __gnu_test;
+  bool test __attribute__((unused)) = true;
+
+  const char* name = "tmp_fifo1";
+  
+  signal(SIGPIPE, SIG_IGN);
+  unlink(name);
+  
+  if (0 != mkfifo(name, S_IRWXU))
+    {
+      VERIFY( false );
+    }
+  
+  semaphore s1, s2;
+  int fval = fork();
+  if (fval == -1)
+    {
+      unlink(name);
+      VERIFY( false );
+    }
+  else if (fval == 0)
+    {
+      filebuf fbout;
+      fbout.open(name, ios_base::in|ios_base::out);
+      VERIFY( fbout.is_open() );
+      fbout.sputn("0123456789", 10);
+      fbout.pubsync();
+      s1.wait();
+      fbout.close();
+      s2.signal();
+      exit(0);
+    }
+
+  UnderBuf fb;
+  fb.open(name, ios_base::in);
+
+  fb.sgetc();
+  streamsize n = fb.pub_showmanyc();
+
+  while (n > 0)
+    {
+      --n;
+      
+      UnderBuf::int_type c = fb.pub_underflow();
+      VERIFY( c != UnderBuf::traits_type::eof() );
+      
+      fb.sbumpc();
+    }
+
+  fb.close();
+  s1.signal();
+  s2.wait();
+
+  return test;
+}
+
+int main() 
+{
+  return !test16();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/2.cc
new file mode 100644
index 000000000..0d36be046
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/2.cc
@@ -0,0 +1,49 @@
+// 2003-06-25 Paolo Carlini <pcarlini@unitus.it>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  filebuf fb_out, fb_in_out;
+  
+  fb_out.open("tmp_underflow.tst", ios::out);
+  fb_out.sputc('S');
+  fb_out.sputc('T');
+  fb_out.close();
+
+  fb_in_out.open("tmp_underflow.tst", ios::in | ios::out);
+  while (fb_in_out.sbumpc() != filebuf::traits_type::eof());
+
+  VERIFY( fb_in_out.sputc('x') == 'x' );
+  fb_in_out.close();
+}
+
+int main()
+{
+  test01();
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/3.cc
new file mode 100644
index 000000000..4de8a4d46
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/3.cc
@@ -0,0 +1,84 @@
+// Copyright (C) 2007, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <cctype>
+#include <locale>
+#include <testsuite_hooks.h>
+
+class Mycvtcc
+: public std::codecvt<char, char, std::mbstate_t>
+{
+protected:
+  virtual result
+  do_in(state_type&,
+	const extern_type* from, const extern_type* from_end,
+	const extern_type*& from_next,
+	intern_type* to, intern_type* to_limit,
+	intern_type*& to_next) const
+  {
+    from_next = from, to_next = to;
+    
+    if (from_next == from_end || to_next == to_limit)
+      return partial;
+    
+    if (std::islower(*from_next))
+      *to_next = std::toupper(*from_next);
+    else
+      *to_next = *from_next;
+    ++from_next, ++to_next;
+    return ok;
+  }
+
+  virtual bool
+  do_always_noconv() const throw()
+  { return false; }
+};
+
+// See Novell Bug 255122
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  const char* name = "tmp_underflow_3.tst";
+  filebuf fbuf, fbufx;
+
+  fbuf.open(name, ios_base::out | ios_base::trunc);
+  VERIFY( fbuf.sputc('a') == 'a' );
+  VERIFY( fbuf.sputc('b') == 'b' );
+  VERIFY( fbuf.sputc('\n') == '\n' );
+  fbuf.close();
+
+  fbufx.pubimbue(locale(locale::classic(), new Mycvtcc));
+  fbufx.open(name, ios_base::in);
+  VERIFY( fbufx.sbumpc() == 'A' );
+  VERIFY( fbufx.sbumpc() == 'B' );
+  VERIFY( fbufx.sbumpc() == '\n' );
+  VERIFY( fbufx.sbumpc() == filebuf::traits_type::eof() );
+  fbufx.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/45841.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/45841.cc
new file mode 100644
index 000000000..a356d626e
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/45841.cc
@@ -0,0 +1,41 @@
+// Copyright (C) 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  filebuf fb_in_out;
+
+  fb_in_out.open("tmp_underflow.tst", ios::in | ios::out | ios::trunc);
+
+  VERIFY( fb_in_out.sputc('x') == 'x' );
+  VERIFY( fb_in_out.sgetc() == filebuf::traits_type::eof() );
+  fb_in_out.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/9027.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/9027.cc
new file mode 100644
index 000000000..25f55493d
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/9027.cc
@@ -0,0 +1,85 @@
+// 2003-05-03  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <cctype>
+#include <testsuite_hooks.h>
+
+class Cvt_to_upper : public std::codecvt<char, char, std::mbstate_t>
+{
+  typedef std::codecvt<char, char, std::mbstate_t> Base;
+
+public:
+  explicit Cvt_to_upper(std::size_t refs = 0)
+  : Base(refs)
+  { }
+
+protected:
+  virtual result
+  do_in(state_type&,
+	const extern_type* from, const extern_type* from_end,
+	const extern_type*& from_next,
+	intern_type* to, intern_type* to_end,
+	intern_type*& to_next) const
+  {
+    while (from < from_end && to < to_end)
+      *to++ = std::toupper(*from++);
+    
+    to_next = to;
+    from_next = from;
+    return from == from_end ? ok : partial;
+  }
+
+  virtual bool
+  do_always_noconv() const throw()
+  {
+    return false;
+  }
+};
+
+// libstdc++/9027
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "filebuf_virtuals-1.txt";
+  locale loc (locale::classic(), new Cvt_to_upper);	
+
+  filebuf fbin;
+  fbin.pubimbue(loc);
+  fbin.open(name, ios_base::in);
+
+  int c;
+  while ((c = fbin.sbumpc()) != EOF)
+    {
+      VERIFY( !islower(c) );
+    }
+  
+  fbin.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/1.cc
new file mode 100644
index 000000000..72c3ecb0a
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/1.cc
@@ -0,0 +1,111 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-09-04  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Test handing of UTF-8 in basic_filebuf::underflow
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char name[] = "tmp_underflow-1.tst";
+
+  const char cstr[] =
+    "\x1\x2\x3\x4\x5\x6\x7\x8\x9\xa\xb\xc\xd\xe\xf\x10\x11\x12\x13"
+    "\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20!\"#$%&"
+    "'()*+,-./0123456789:;<=>?@}~\x7f\xc2\x80\xc2\x81\xc2\x82\xc2"
+    "\x83\xc2\x84\xc2\x85\xc2\x86\xc2\x87\xc2\x88\xc2\x89\xc2\x8a"
+    "\xc2\x8b\xc2\x8c\xc2\x8d\xc2\x8e\xc2\x8f\xc2\x90\xc2\x91\xc2"
+    "\x92\xc2\x93\xc2\x94\xc2\x95\xc2\x96\xc2\x97\xc2\x98\xc2\x99"
+    "\xc2\x9a\xc2\x9b\xc2\x9c\xc3\xba\xc3\xbb\xc3\xbc\xc3\xbd\xc3"
+    "\xbe\xc3\xbf\xc4\x80\xc4\x81\xc4\x82\xc4\x83\xc4\x84\xc4\x85"
+    "\xc4\x86\xc4\x87\xc4\x88\xc4\x89\xc4\x8a\xc4\x8b\xc4\x8c\xc4"
+    "\x8d\xc4\x8e\xc4\x8f\xc4\x90\xc4\x91\xc4\x92\xc4\x93\xc4\x94"
+    "\xc4\x95\xc4\x96\xc4\x97\xc4\x98\xc4\x99\xdf\xb8\xdf\xb9\xdf"
+    "\xba\xdf\xbb\xdf\xbc\xdf\xbd\xdf\xbe\xdf\xbf\xe0\xa0\x80\xe0"
+    "\xa0\x81\xe0\xa0\x82\xe0\xa0\x83\xe0\xa0\x84\xe0\xa0\x85\xe0"
+    "\xa0\x86\xe0\xa0\x87\xe0\xa0\x88\xe0\xa0\x89\xe0\xa0\x8a\xe0"
+    "\xa0\x8b\xe0\xa0\x8c\xe0\xa0\x8d\xe0\xa0\x8e\xe0\xa0\x8f\xe0"
+    "\xa0\x90\xe0\xa0\x91\xe0\xa0\x92\xe0\xa0\x93\xe0\xa0\x94\xe0"
+    "\xa0\x95\xe0\xa0\x96\xe0\xa0\x97\x1\x2\x4\x8\x10\x20@\xc2\x80"
+    "\xc4\x80\xc8\x80\xd0\x80\xe0\xa0\x80\xe1\x80\x80\xe2\x80\x80"
+    "\xe4\x80\x80\xe8\x80\x80\xf0\x90\x80\x80\xf0\xa0\x80\x80\xf1"
+    "\x80\x80\x80\xf2\x80\x80\x80\xf4\x80\x80\x80\xf8\x88\x80\x80"
+    "\x80\xf8\x90\x80\x80\x80\xf8\xa0\x80\x80\x80\xf9\x80\x80\x80"
+    "\x80\xfa\x80\x80\x80\x80\xfc\x84\x80\x80\x80\x80\xfc\x88\x80"
+    "\x80\x80\x80\xfc\x90\x80\x80\x80\x80\xfc\xa0\x80\x80\x80\x80"
+    "\xfd\x80\x80\x80\x80\x80";
+
+  const wchar_t wstr[] = {
+    0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc,
+    0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, L'!',
+    L'"', L'#', L'$', L'%', L'&', L'\'', L'(', L')', L'*', L'+',
+    L',', L'-', L'.', L'/', L'0', L'1', L'2', L'3', L'4', L'5',
+    L'6', L'7', L'8', L'9', L':', L';', L'<', L'=', L'>', L'?',
+    L'@', L'}', L'~', 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
+    0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+    0x9a, 0x9b, 0x9c, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 0x100,
+    0x101, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107, 0x108, 0x109,
+    0x10a, 0x10b, 0x10c, 0x10d, 0x10e, 0x10f, 0x110, 0x111, 0x112,
+    0x113, 0x114, 0x115, 0x116, 0x117, 0x118, 0x119, 0x7f8, 0x7f9,
+    0x7fa, 0x7fb, 0x7fc, 0x7fd, 0x7fe, 0x7ff, 0x800, 0x801, 0x802,
+    0x803, 0x804, 0x805, 0x806, 0x807, 0x808, 0x809, 0x80a, 0x80b,
+    0x80c, 0x80d, 0x80e, 0x80f, 0x810, 0x811, 0x812, 0x813, 0x814,
+    0x815, 0x816, 0x817, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, L'@',
+    0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000,
+    0x10000, 0x20000, 0x40000, 0x80000, 0x100000, 0x200000, 0x400000,
+    0x800000, 0x1000000, 0x2000000, 0x4000000, 0x8000000, 0x10000000,
+    0x20000000, 0x40000000, 0x0
+  };
+
+  const size_t clen = sizeof(cstr) / sizeof(cstr[0]);
+  const size_t wlen = sizeof(wstr) / sizeof(wstr[0]);
+
+  locale loc = locale("se_NO.UTF-8");
+
+  FILE* file = fopen(name, "w");
+  fwrite(cstr, 1, clen, file);
+  fclose(file);
+
+  wchar_t wbuf[wlen + 1];
+  
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.open(name, ios_base::in);
+  streamsize n = fb.sgetn(wbuf, wlen + 1);
+  fb.close();
+
+  VERIFY( n == static_cast<streamsize>(wlen) );
+  VERIFY( !wmemcmp(wbuf, wstr, wlen) );
+}
+
+int main ()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-1.cc
new file mode 100644
index 000000000..55e226705
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-1.cc
@@ -0,0 +1,50 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_01[] = "tmp_11389-1";
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbout;
+  fbout.open(name_01, ios_base::out);
+  fbout.sputc('a');
+  fbout.close();
+  
+  wfilebuf fbin;
+  locale loc(locale("en_US.UTF-8"));
+  fbin.pubimbue(loc);
+  fbin.open(name_01, ios_base::in);
+  VERIFY( fbin.sbumpc() == L'a' );
+  VERIFY( fbin.sgetc() == wfilebuf::traits_type::eof() );
+  fbin.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-2.cc
new file mode 100644
index 000000000..e4527ee69
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-2.cc
@@ -0,0 +1,52 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_02[] = "tmp_11389-2";
+
+void test02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbout;
+  fbout.open(name_02, ios_base::out);
+  fbout.sputc('a');
+  fbout.sputc('b');
+  fbout.close();
+  
+  wfilebuf fbin;
+  locale loc(locale("en_US.UTF-8"));
+  fbin.pubimbue(loc);
+  fbin.open(name_02, ios_base::in);
+  VERIFY( fbin.sbumpc() == L'a' );
+  VERIFY( fbin.sbumpc() == L'b' );
+  VERIFY( fbin.sgetc() == wfilebuf::traits_type::eof() );
+  fbin.close();
+}
+
+int main()
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-3.cc
new file mode 100644
index 000000000..45bb4bdf5
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-3.cc
@@ -0,0 +1,51 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_03[] = "tmp_11389-3";
+
+void test03()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbout;
+  fbout.open(name_03, ios_base::out);
+  fbout.sputc('a');
+  fbout.close();
+  
+  wfilebuf fbin;
+  locale loc(locale("en_US.UTF-8"));
+  fbin.pubimbue(loc);
+  fbin.pubsetbuf(0, 0);
+  fbin.open(name_03, ios_base::in);
+  VERIFY( fbin.sbumpc() == L'a' );
+  VERIFY( fbin.sgetc() == wfilebuf::traits_type::eof() );
+  fbin.close();
+}
+
+int main()
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-4.cc
new file mode 100644
index 000000000..637f89806
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11389-4.cc
@@ -0,0 +1,53 @@
+// { dg-require-namedlocale "en_US.UTF-8" }
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+const char name_04[] = "tmp_11389-4";
+
+void test04()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbout;
+  fbout.open(name_04, ios_base::out);
+  fbout.sputc('a');
+  fbout.sputc('b');
+  fbout.close();
+  
+  wfilebuf fbin;
+  locale loc(locale("en_US.UTF-8"));
+  fbin.pubimbue(loc);
+  fbin.pubsetbuf(0, 0);
+  fbin.open(name_04, ios_base::in);
+  VERIFY( fbin.sbumpc() == L'a' );
+  VERIFY( fbin.sbumpc() == L'b' );
+  VERIFY( fbin.sgetc() == wfilebuf::traits_type::eof() );
+  fbin.close();
+}
+
+int main()
+{
+  test04();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11544-1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11544-1.cc
new file mode 100644
index 000000000..7a27acd6f
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11544-1.cc
@@ -0,0 +1,184 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+template <typename InternT, typename StateT = mbstate_t>
+class checksumcvt : public std::codecvt<InternT, char, StateT>
+{
+  typedef std::codecvt<InternT, char, StateT> Base;
+  static const size_t width = sizeof(InternT) + 1;
+
+public:
+  typedef InternT intern_type;
+  typedef char extern_type;
+
+  explicit checksumcvt(size_t refs = 0)
+  : Base(refs)
+  { }
+
+protected:
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_out(StateT&, const intern_type* from,
+	 const intern_type* from_end, const intern_type*& from_next,
+	 extern_type* to, extern_type* to_end,
+	 extern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(from_end - from),
+			  static_cast<size_t>(to_end - to) / width);
+
+    while (len--)
+      {
+	const char* p = reinterpret_cast<const char*>(from);
+	unsigned char checksum = 0;
+				
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    *to++ = p[i];
+	    checksum ^= static_cast<unsigned char>(p[i]);
+	  }
+
+	*to++ = checksum;
+	++from;
+      }
+
+    from_next = from;
+    to_next = to;
+    return from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
+           : std::codecvt<InternT, char, StateT>::partial;
+  }
+
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_unshift(StateT&, extern_type* to,
+	     extern_type*, extern_type*& to_next) const
+  {
+    to_next = to;
+    return std::codecvt<InternT, char, StateT>::ok;
+  }
+
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_in(StateT&, const extern_type* from,
+	const extern_type* from_end, const extern_type*& from_next,
+	intern_type* to, intern_type* to_end,
+	intern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(to_end - to),
+			  static_cast<size_t>(from_end - from) / width);
+			
+    while (len)
+      {
+	const char* f = from;
+	intern_type tmp;
+	char* p = reinterpret_cast<char*>(&tmp);
+	unsigned char checksum = 0;
+
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    p[i] = *f;
+	    checksum ^= static_cast<unsigned char>(*f++);
+	  }
+
+	if (*f++ != checksum)
+	  break;
+
+	from = f;
+	*to++ = tmp;
+	len--;
+      }
+
+    from_next = from;
+    to_next = to;
+    return len ? std::codecvt<InternT, char, StateT>::error :
+      (from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
+       : std::codecvt<InternT, char, StateT>::partial);
+  }
+
+  virtual int
+  do_encoding() const throw()
+  { return width; }
+
+  virtual int
+  do_length(StateT&, const extern_type* from,
+	    const extern_type* end, size_t max) const
+  {
+    size_t len = std::min(max, static_cast<size_t>(end - from) / width);
+
+    int ret = 0;
+    while (len--)
+      {
+	unsigned char checksum = 0;
+
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    checksum ^= static_cast<unsigned char>(*from++);
+	  }
+
+	if (*from++ != checksum)
+	  break;
+
+	ret++;
+      }
+
+    return ret;
+  }
+
+  virtual int
+  do_max_length() const throw()
+  { return width; }
+
+  virtual bool
+  do_always_noconv() const throw()
+  { return false; }
+};
+
+// libstdc++/11544 (incomplete character in file)
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc(locale::classic(), new checksumcvt<wchar_t>);
+
+  const char* name = "tmp_11544-1";
+  
+  FILE* f = fopen(name, "w");
+  putc('a', f);
+  fclose(f);
+  
+  wifstream in;
+  in.imbue(loc);
+  in.open(name);
+  
+  VERIFY( in.good() );
+  in.get();
+  VERIFY( !in.good() );
+  VERIFY( in.bad() );
+  VERIFY( !in.eof() );
+  
+  in.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11544-2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11544-2.cc
new file mode 100644
index 000000000..f6a2eaca9
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11544-2.cc
@@ -0,0 +1,184 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+template <typename InternT, typename StateT = mbstate_t>
+class checksumcvt : public std::codecvt<InternT, char, StateT>
+{
+  typedef std::codecvt<InternT, char, StateT> Base;
+  static const size_t width = sizeof(InternT) + 1;
+
+public:
+  typedef InternT intern_type;
+  typedef char extern_type;
+
+  explicit checksumcvt(size_t refs = 0)
+  : Base(refs)
+  { }
+
+protected:
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_out(StateT&, const intern_type* from,
+	 const intern_type* from_end, const intern_type*& from_next,
+	 extern_type* to, extern_type* to_end,
+	 extern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(from_end - from),
+			  static_cast<size_t>(to_end - to) / width);
+
+    while (len--)
+      {
+	const char* p = reinterpret_cast<const char*>(from);
+	unsigned char checksum = 0;
+				
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    *to++ = p[i];
+	    checksum ^= static_cast<unsigned char>(p[i]);
+	  }
+
+	*to++ = checksum;
+	++from;
+      }
+
+    from_next = from;
+    to_next = to;
+    return from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
+           : std::codecvt<InternT, char, StateT>::partial;
+  }
+
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_unshift(StateT&, extern_type* to,
+	     extern_type*, extern_type*& to_next) const
+  {
+    to_next = to;
+    return std::codecvt<InternT, char, StateT>::ok;
+  }
+
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_in(StateT&, const extern_type* from,
+	const extern_type* from_end, const extern_type*& from_next,
+	intern_type* to, intern_type* to_end,
+	intern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(to_end - to),
+			  static_cast<size_t>(from_end - from) / width);
+			
+    while (len)
+      {
+	const char* f = from;
+	intern_type tmp;
+	char* p = reinterpret_cast<char*>(&tmp);
+	unsigned char checksum = 0;
+
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    p[i] = *f;
+	    checksum ^= static_cast<unsigned char>(*f++);
+	  }
+
+	if (*f++ != checksum)
+	  break;
+
+	from = f;
+	*to++ = tmp;
+	len--;
+      }
+
+    from_next = from;
+    to_next = to;
+    return len ? std::codecvt<InternT, char, StateT>::error :
+      (from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
+       : std::codecvt<InternT, char, StateT>::partial);
+  }
+
+  virtual int
+  do_encoding() const throw()
+  { return width; }
+
+  virtual int
+  do_length(StateT&, const extern_type* from,
+	    const extern_type* end, size_t max) const
+  {
+    size_t len = std::min(max, static_cast<size_t>(end - from) / width);
+
+    int ret = 0;
+    while (len--)
+      {
+	unsigned char checksum = 0;
+
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    checksum ^= static_cast<unsigned char>(*from++);
+	  }
+
+	if (*from++ != checksum)
+	  break;
+
+	ret++;
+      }
+
+    return ret;
+  }
+
+  virtual int
+  do_max_length() const throw()
+  { return width; }
+
+  virtual bool
+  do_always_noconv() const throw()
+  { return false; }
+};
+
+// libstdc++/11544 (invalid byte sequence in file)
+void test02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc(locale::classic(), new checksumcvt<wchar_t>);
+  
+  const char* name = "tmp_11544-2";
+  
+  FILE* f = fopen(name, "w");
+  VERIFY( fwrite("aaaab", 1, 5, f) == 5 );
+  fclose(f);
+  
+  wifstream in;
+  in.imbue(loc);
+  in.open(name);
+  
+  VERIFY( in.good() );
+  in.get();
+  VERIFY( !in.good() );
+  VERIFY( in.bad() );
+  VERIFY( !in.eof() );
+  
+  in.close();
+}
+
+int main()
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11603.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11603.cc
new file mode 100644
index 000000000..116c404a5
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11603.cc
@@ -0,0 +1,201 @@
+// Copyright (C) 2003, 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+// { dg-require-binary-io "" }
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+template <typename InternT, typename StateT = std::mbstate_t>
+class checksumcvt : public std::codecvt<InternT, char, StateT>
+{
+  typedef std::codecvt<InternT, char, StateT> Base;
+  static const std::size_t width = sizeof(InternT) + 1;
+
+public:
+  typedef InternT intern_type;
+  typedef char extern_type;
+
+  explicit checksumcvt(std::size_t refs = 0)
+    : Base(refs)
+  { }
+
+protected:
+  virtual std::codecvt_base::result
+  do_out(StateT&, const intern_type* from,
+	 const intern_type* from_end, const intern_type*& from_next,
+	 extern_type* to, extern_type* to_end,
+	 extern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(from_end - from),
+			  static_cast<size_t>(to_end - to) / width);
+
+    while (len--)
+      {
+	const char* p =
+	  reinterpret_cast<const char*>(from);
+	unsigned char checksum = 0;
+				
+	for (std::size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    *to++ = p[i];
+	    checksum ^= static_cast<unsigned char>(p[i]);
+	  }
+
+	*to++ = checksum;
+	++from;
+      }
+
+    from_next = from;
+    to_next = to;
+    return from_next == from_end ? std::codecvt_base::ok 
+                                 : std::codecvt_base::partial;
+  }
+
+  virtual std::codecvt_base::result
+  do_unshift(StateT&, extern_type* to,
+	     extern_type*, extern_type*& to_next) const
+  {
+    to_next = to;
+    return std::codecvt_base::ok;
+  }
+
+  virtual std::codecvt_base::result
+  do_in(StateT&, const extern_type* from,
+	const extern_type* from_end, const extern_type*& from_next,
+	intern_type* to, intern_type* to_end,
+	intern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(to_end - to),
+			  static_cast<size_t>(from_end - from) / width);
+			
+    while (len)
+      {
+	const char* f = from;
+	intern_type tmp;
+	char* p = reinterpret_cast<char*>(&tmp);
+	unsigned char checksum = 0;
+
+	for (std::size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    p[i] = *f;
+	    checksum ^= static_cast<unsigned char>(*f++);
+	  }
+
+	if (*f++ != checksum)
+	  break;
+
+	from = f;
+	*to++ = tmp;
+	len--;
+      }
+
+    from_next = from;
+    to_next = to;
+    return len ? std::codecvt_base::error :
+      (from_next == from_end ? std::codecvt_base::ok
+                             : std::codecvt_base::partial);
+  }
+
+  virtual int
+  do_encoding() const throw()
+  { return width; }
+
+  virtual int
+  do_length(const StateT&, const extern_type* from,
+	    const extern_type* end, size_t max) const
+  {
+    size_t len = std::min(max,
+			  static_cast<size_t>(end - from) / width);
+
+    int ret = 0;
+    while (len--)
+      {
+	unsigned char checksum = 0;
+
+	for (std::size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    checksum ^= static_cast<unsigned char>(*from++);
+	  }
+
+	if (*from++ != checksum)
+	  break;
+
+	ret++;
+      }
+
+    return ret;
+  }
+
+  virtual int
+  do_max_length() const throw()
+  { return width; }
+
+  virtual bool
+  do_always_noconv() const throw()
+  { return false; }
+};
+
+class Buf : public std::wfilebuf
+{
+public:
+  std::streamsize pub_showmanyc()
+  { return showmanyc(); }
+  std::wfilebuf::int_type pub_underflow()
+  { return underflow(); }
+};
+
+// libstdc++/11603
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  filebuf fbout;
+  fbout.open("tmp_11603", ios_base::out);
+  fbout.sputn("aaaab", 5);
+  fbout.close();
+
+  locale loc(locale::classic(), new checksumcvt<wchar_t>);
+  
+  Buf fb;
+  fb.pubimbue(loc);
+  fb.open("tmp_11603", ios_base::in);
+  VERIFY( fb.pub_showmanyc() == 1 );
+  
+  try
+    {
+      wfilebuf::int_type ret = fb.pub_underflow();
+      VERIFY( ret != wfilebuf::traits_type::eof() );
+      fb.sbumpc();
+      ret = fb.pub_underflow();
+      VERIFY( ret == wfilebuf::traits_type::eof() );
+    }
+  catch (...)
+    { }
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/2.cc
new file mode 100644
index 000000000..c6f30442c
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/2.cc
@@ -0,0 +1,112 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-09-04  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Test handing of UTF-8 in unbuffered basic_filebuf::underflow
+void test02()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char name[] = "tmp_underflow-2.tst";
+
+  const char cstr[] =
+    "\x1\x2\x3\x4\x5\x6\x7\x8\x9\xa\xb\xc\xd\xe\xf\x10\x11\x12\x13"
+    "\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20!\"#$%&"
+    "'()*+,-./0123456789:;<=>?@}~\x7f\xc2\x80\xc2\x81\xc2\x82\xc2"
+    "\x83\xc2\x84\xc2\x85\xc2\x86\xc2\x87\xc2\x88\xc2\x89\xc2\x8a"
+    "\xc2\x8b\xc2\x8c\xc2\x8d\xc2\x8e\xc2\x8f\xc2\x90\xc2\x91\xc2"
+    "\x92\xc2\x93\xc2\x94\xc2\x95\xc2\x96\xc2\x97\xc2\x98\xc2\x99"
+    "\xc2\x9a\xc2\x9b\xc2\x9c\xc3\xba\xc3\xbb\xc3\xbc\xc3\xbd\xc3"
+    "\xbe\xc3\xbf\xc4\x80\xc4\x81\xc4\x82\xc4\x83\xc4\x84\xc4\x85"
+    "\xc4\x86\xc4\x87\xc4\x88\xc4\x89\xc4\x8a\xc4\x8b\xc4\x8c\xc4"
+    "\x8d\xc4\x8e\xc4\x8f\xc4\x90\xc4\x91\xc4\x92\xc4\x93\xc4\x94"
+    "\xc4\x95\xc4\x96\xc4\x97\xc4\x98\xc4\x99\xdf\xb8\xdf\xb9\xdf"
+    "\xba\xdf\xbb\xdf\xbc\xdf\xbd\xdf\xbe\xdf\xbf\xe0\xa0\x80\xe0"
+    "\xa0\x81\xe0\xa0\x82\xe0\xa0\x83\xe0\xa0\x84\xe0\xa0\x85\xe0"
+    "\xa0\x86\xe0\xa0\x87\xe0\xa0\x88\xe0\xa0\x89\xe0\xa0\x8a\xe0"
+    "\xa0\x8b\xe0\xa0\x8c\xe0\xa0\x8d\xe0\xa0\x8e\xe0\xa0\x8f\xe0"
+    "\xa0\x90\xe0\xa0\x91\xe0\xa0\x92\xe0\xa0\x93\xe0\xa0\x94\xe0"
+    "\xa0\x95\xe0\xa0\x96\xe0\xa0\x97\x1\x2\x4\x8\x10\x20@\xc2\x80"
+    "\xc4\x80\xc8\x80\xd0\x80\xe0\xa0\x80\xe1\x80\x80\xe2\x80\x80"
+    "\xe4\x80\x80\xe8\x80\x80\xf0\x90\x80\x80\xf0\xa0\x80\x80\xf1"
+    "\x80\x80\x80\xf2\x80\x80\x80\xf4\x80\x80\x80\xf8\x88\x80\x80"
+    "\x80\xf8\x90\x80\x80\x80\xf8\xa0\x80\x80\x80\xf9\x80\x80\x80"
+    "\x80\xfa\x80\x80\x80\x80\xfc\x84\x80\x80\x80\x80\xfc\x88\x80"
+    "\x80\x80\x80\xfc\x90\x80\x80\x80\x80\xfc\xa0\x80\x80\x80\x80"
+    "\xfd\x80\x80\x80\x80\x80";
+
+  const wchar_t wstr[] = {
+    0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc,
+    0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, L'!',
+    L'"', L'#', L'$', L'%', L'&', L'\'', L'(', L')', L'*', L'+',
+    L',', L'-', L'.', L'/', L'0', L'1', L'2', L'3', L'4', L'5',
+    L'6', L'7', L'8', L'9', L':', L';', L'<', L'=', L'>', L'?',
+    L'@', L'}', L'~', 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
+    0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+    0x9a, 0x9b, 0x9c, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 0x100,
+    0x101, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107, 0x108, 0x109,
+    0x10a, 0x10b, 0x10c, 0x10d, 0x10e, 0x10f, 0x110, 0x111, 0x112,
+    0x113, 0x114, 0x115, 0x116, 0x117, 0x118, 0x119, 0x7f8, 0x7f9,
+    0x7fa, 0x7fb, 0x7fc, 0x7fd, 0x7fe, 0x7ff, 0x800, 0x801, 0x802,
+    0x803, 0x804, 0x805, 0x806, 0x807, 0x808, 0x809, 0x80a, 0x80b,
+    0x80c, 0x80d, 0x80e, 0x80f, 0x810, 0x811, 0x812, 0x813, 0x814,
+    0x815, 0x816, 0x817, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, L'@',
+    0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000,
+    0x10000, 0x20000, 0x40000, 0x80000, 0x100000, 0x200000, 0x400000,
+    0x800000, 0x1000000, 0x2000000, 0x4000000, 0x8000000, 0x10000000,
+    0x20000000, 0x40000000, 0x0
+  };
+
+  const size_t clen = sizeof(cstr) / sizeof(cstr[0]);
+  const size_t wlen = sizeof(wstr) / sizeof(wstr[0]);
+
+  locale loc = locale("se_NO.UTF-8");
+
+  FILE* file = fopen(name, "w");
+  fwrite(cstr, 1, clen, file);
+  fclose(file);
+
+  wchar_t wbuf[wlen + 1];
+  
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.pubsetbuf(0, 0);
+  fb.open(name, ios_base::in);
+  streamsize n = fb.sgetn(wbuf, wlen + 1);
+  fb.close();
+
+  VERIFY( n == static_cast<streamsize>(wlen) );
+  VERIFY( !wmemcmp(wbuf, wstr, wlen) );
+}
+
+int main ()
+{
+  test02();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/3.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/3.cc
new file mode 100644
index 000000000..42892e4ac
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/3.cc
@@ -0,0 +1,117 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-09-04  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Test handing of UTF-8 in basic_filebuf::underflow
+void test03()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char name[] = "tmp_underflow-3.tst";
+
+  const char cstr[] =
+    "\x1\x2\x3\x4\x5\x6\x7\x8\x9\xa\xb\xc\xd\xe\xf\x10\x11\x12\x13"
+    "\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20!\"#$%&"
+    "'()*+,-./0123456789:;<=>?@}~\x7f\xc2\x80\xc2\x81\xc2\x82\xc2"
+    "\x83\xc2\x84\xc2\x85\xc2\x86\xc2\x87\xc2\x88\xc2\x89\xc2\x8a"
+    "\xc2\x8b\xc2\x8c\xc2\x8d\xc2\x8e\xc2\x8f\xc2\x90\xc2\x91\xc2"
+    "\x92\xc2\x93\xc2\x94\xc2\x95\xc2\x96\xc2\x97\xc2\x98\xc2\x99"
+    "\xc2\x9a\xc2\x9b\xc2\x9c\xc3\xba\xc3\xbb\xc3\xbc\xc3\xbd\xc3"
+    "\xbe\xc3\xbf\xc4\x80\xc4\x81\xc4\x82\xc4\x83\xc4\x84\xc4\x85"
+    "\xc4\x86\xc4\x87\xc4\x88\xc4\x89\xc4\x8a\xc4\x8b\xc4\x8c\xc4"
+    "\x8d\xc4\x8e\xc4\x8f\xc4\x90\xc4\x91\xc4\x92\xc4\x93\xc4\x94"
+    "\xc4\x95\xc4\x96\xc4\x97\xc4\x98\xc4\x99\xdf\xb8\xdf\xb9\xdf"
+    "\xba\xdf\xbb\xdf\xbc\xdf\xbd\xdf\xbe\xdf\xbf\xe0\xa0\x80\xe0"
+    "\xa0\x81\xe0\xa0\x82\xe0\xa0\x83\xe0\xa0\x84\xe0\xa0\x85\xe0"
+    "\xa0\x86\xe0\xa0\x87\xe0\xa0\x88\xe0\xa0\x89\xe0\xa0\x8a\xe0"
+    "\xa0\x8b\xe0\xa0\x8c\xe0\xa0\x8d\xe0\xa0\x8e\xe0\xa0\x8f\xe0"
+    "\xa0\x90\xe0\xa0\x91\xe0\xa0\x92\xe0\xa0\x93\xe0\xa0\x94\xe0"
+    "\xa0\x95\xe0\xa0\x96\xe0\xa0\x97\x1\x2\x4\x8\x10\x20@\xc2\x80"
+    "\xc4\x80\xc8\x80\xd0\x80\xe0\xa0\x80\xe1\x80\x80\xe2\x80\x80"
+    "\xe4\x80\x80\xe8\x80\x80\xf0\x90\x80\x80\xf0\xa0\x80\x80\xf1"
+    "\x80\x80\x80\xf2\x80\x80\x80\xf4\x80\x80\x80\xf8\x88\x80\x80"
+    "\x80\xf8\x90\x80\x80\x80\xf8\xa0\x80\x80\x80\xf9\x80\x80\x80"
+    "\x80\xfa\x80\x80\x80\x80\xfc\x84\x80\x80\x80\x80\xfc\x88\x80"
+    "\x80\x80\x80\xfc\x90\x80\x80\x80\x80\xfc\xa0\x80\x80\x80\x80"
+    "\xfd\x80\x80\x80\x80\x80";
+
+  const wchar_t wstr[] = {
+    0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc,
+    0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, L'!',
+    L'"', L'#', L'$', L'%', L'&', L'\'', L'(', L')', L'*', L'+',
+    L',', L'-', L'.', L'/', L'0', L'1', L'2', L'3', L'4', L'5',
+    L'6', L'7', L'8', L'9', L':', L';', L'<', L'=', L'>', L'?',
+    L'@', L'}', L'~', 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
+    0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+    0x9a, 0x9b, 0x9c, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 0x100,
+    0x101, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107, 0x108, 0x109,
+    0x10a, 0x10b, 0x10c, 0x10d, 0x10e, 0x10f, 0x110, 0x111, 0x112,
+    0x113, 0x114, 0x115, 0x116, 0x117, 0x118, 0x119, 0x7f8, 0x7f9,
+    0x7fa, 0x7fb, 0x7fc, 0x7fd, 0x7fe, 0x7ff, 0x800, 0x801, 0x802,
+    0x803, 0x804, 0x805, 0x806, 0x807, 0x808, 0x809, 0x80a, 0x80b,
+    0x80c, 0x80d, 0x80e, 0x80f, 0x810, 0x811, 0x812, 0x813, 0x814,
+    0x815, 0x816, 0x817, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, L'@',
+    0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000,
+    0x10000, 0x20000, 0x40000, 0x80000, 0x100000, 0x200000, 0x400000,
+    0x800000, 0x1000000, 0x2000000, 0x4000000, 0x8000000, 0x10000000,
+    0x20000000, 0x40000000, 0x0
+  };
+
+  const size_t clen = sizeof(cstr) / sizeof(cstr[0]);
+  const size_t wlen = sizeof(wstr) / sizeof(wstr[0]);
+
+  const int loops = 2 * BUFSIZ / wlen;
+  locale loc = locale("se_NO.UTF-8");
+
+  FILE* file = fopen(name, "w");
+  for (int i = 0; i < loops; ++i)
+    fwrite(cstr, 1, clen, file);
+  fclose(file);
+
+  wchar_t wbuf[wlen];
+  
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.open(name, ios_base::in);
+  for (int i = 0; i < loops; ++i)
+    {
+      streamsize n = fb.sgetn(wbuf, wlen);
+      VERIFY( n == static_cast<streamsize>(wlen) );
+      VERIFY( !wmemcmp(wbuf, wstr, wlen) );
+    }
+
+  VERIFY( fb.sgetc() == wfilebuf::traits_type::eof() );
+  fb.close();
+}
+
+int main ()
+{
+  test03();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/4.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/4.cc
new file mode 100644
index 000000000..6e63db09d
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/4.cc
@@ -0,0 +1,55 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-09-04  Petur Runolfsson  <peturr02@ru.is>
+// Adapted from 27_io/basic_filebuf/underflow/char/2.cc
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  locale loc (locale("se_NO.UTF-8"));
+  wfilebuf fb_out, fb_in_out;
+  fb_out.pubimbue(loc);
+  fb_in_out.pubimbue(loc);
+  
+  fb_out.open("tmp_underflow.tst", ios::out);
+  fb_out.sputc(L'S');
+  fb_out.sputc(L'T');
+  fb_out.close();
+
+  fb_in_out.open("tmp_underflow.tst", ios::in | ios::out);
+  while (fb_in_out.sbumpc() != wfilebuf::traits_type::eof());
+
+  VERIFY( fb_in_out.sputc(L'x') == L'x' );
+  fb_in_out.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/45841.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/45841.cc
new file mode 100644
index 000000000..2d7cb7af2
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/45841.cc
@@ -0,0 +1,41 @@
+// Copyright (C) 2010 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-require-fileio "" }
+
+#include <fstream>
+#include <testsuite_hooks.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using namespace std;
+
+  wfilebuf fb_in_out;
+
+  fb_in_out.open("tmp_underflow.tst", ios::in | ios::out | ios::trunc);
+
+  VERIFY( fb_in_out.sputc(L'x') == L'x' );
+  VERIFY( fb_in_out.sgetc() == wfilebuf::traits_type::eof() );
+  fb_in_out.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/5.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/5.cc
new file mode 100644
index 000000000..4c4b8d3b4
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/5.cc
@@ -0,0 +1,74 @@
+// { dg-require-namedlocale "se_NO.UTF-8" }
+
+// 2003-09-04  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <locale>
+#include <fstream>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Test that unbuffered really means unbuffered for UTF-8
+void test05()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_underflow-5";
+
+  wfilebuf fb;
+  fb.pubsetbuf(0, 0);
+  fb.pubimbue(locale("se_NO.UTF-8"));
+
+  FILE* file = fopen(name, "w");
+  setvbuf(file, 0, _IONBF, 0);
+  fputs("abcde", file);
+
+  fb.open(name, ios_base::in);
+  VERIFY( fb.sbumpc() == L'a' );
+  
+  fseek(file, 1, SEEK_SET);
+  fputc('0', file);
+
+  VERIFY( fb.sbumpc() == L'0' );
+  VERIFY( fb.sbumpc() == L'c' );
+
+  fputc('1', file);
+  fputc('2', file);
+
+  VERIFY( fb.sbumpc() == L'2' );
+  VERIFY( fb.sbumpc() == L'e' );
+  VERIFY( fb.sbumpc() == WEOF );
+
+  fputc('3', file);
+  fputc('4', file);
+
+  VERIFY( fb.sbumpc() == L'4' );
+  VERIFY( fb.sbumpc() == WEOF );
+
+  fb.close();
+  fclose(file);
+}
+
+int main()
+{
+  test05();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/9178.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/9178.cc
new file mode 100644
index 000000000..344db32d7
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/9178.cc
@@ -0,0 +1,204 @@
+// Copyright (C) 2003, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <string>
+#include <iterator>
+#include <algorithm>
+#include <locale>
+#include <testsuite_hooks.h>
+
+template <typename InternT, typename StateT = mbstate_t>
+class checksumcvt : public std::codecvt<InternT, char, StateT>
+{
+  typedef std::codecvt<InternT, char, StateT> Base;
+  static const size_t width = sizeof(InternT) + 1;
+
+public:
+  typedef InternT intern_type;
+  typedef char extern_type;
+
+  explicit checksumcvt(size_t refs = 0)
+  : Base(refs)
+  { }
+
+protected:
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_out(StateT&, const intern_type* from,
+	 const intern_type* from_end, const intern_type*& from_next,
+	 extern_type* to, extern_type* to_end,
+	 extern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(from_end - from),
+			  static_cast<size_t>(to_end - to) / width);
+
+    while (len--)
+      {
+	const char* p = reinterpret_cast<const char*>(from);
+	unsigned char checksum = 0;
+				
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    *to++ = p[i];
+	    checksum ^= static_cast<unsigned char>(p[i]);
+	  }
+
+	*to++ = checksum;
+	++from;
+      }
+
+    from_next = from;
+    to_next = to;
+    return from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
+           : std::codecvt<InternT, char, StateT>::partial;
+  }
+
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_unshift(StateT&, extern_type* to,
+	     extern_type*, extern_type*& to_next) const
+  {
+    to_next = to;
+    return std::codecvt<InternT, char, StateT>::ok;
+  }
+
+  virtual typename std::codecvt<InternT, char, StateT>::result
+  do_in(StateT&, const extern_type* from,
+	const extern_type* from_end, const extern_type*& from_next,
+	intern_type* to, intern_type* to_end,
+	intern_type*& to_next) const
+  {
+    size_t len = std::min(static_cast<size_t>(to_end - to),
+			  static_cast<size_t>(from_end - from) / width);
+			
+    while (len)
+      {
+	const char* f = from;
+	intern_type tmp;
+	char* p = reinterpret_cast<char*>(&tmp);
+	unsigned char checksum = 0;
+
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    p[i] = *f;
+	    checksum ^= static_cast<unsigned char>(*f++);
+	  }
+
+	if (*f++ != checksum)
+	  break;
+
+	from = f;
+	*to++ = tmp;
+	len--;
+      }
+
+    from_next = from;
+    to_next = to;
+    return len ? std::codecvt<InternT, char, StateT>::error :
+      (from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
+       : std::codecvt<InternT, char, StateT>::partial);
+  }
+
+  virtual int
+  do_encoding() const throw()
+  {
+    return width;
+  }
+
+  virtual int
+  do_length(StateT&, const extern_type* from,
+	    const extern_type* end, size_t max) const
+  {
+    size_t len = std::min(max, static_cast<size_t>(end - from) / width);
+
+    int ret = 0;
+    while (len--)
+      {
+	unsigned char checksum = 0;
+
+	for (size_t i = 0; i < sizeof(intern_type); ++i)
+	  {
+	    checksum ^= static_cast<unsigned char>(*from++);
+	  }
+
+	if (*from++ != checksum)
+	  break;
+
+	ret++;
+      }
+
+    return ret;
+  }
+
+  virtual int
+  do_max_length() const throw()
+  {
+    return width;
+  }
+
+  virtual bool
+  do_always_noconv() const throw()
+  {
+    return false;
+  }
+};
+
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  locale loc;
+  loc = locale(loc, new checksumcvt<wchar_t>);
+
+  wfilebuf fbuf1;
+  fbuf1.pubimbue(loc);
+  fbuf1.open("tmp_9178", ios_base::out | ios_base::trunc);
+	
+  string tmpstr = "abcdefghijklmnopqrstuvwxyz0123456789 \t\n";
+
+  wifstream stream;
+  wstring str1;
+
+  while (str1.length() < 20000) 
+    {
+      transform(tmpstr.begin(), tmpstr.end(),
+		back_inserter(str1),
+		bind1st(std::mem_fun(&std::wios::widen), &stream));
+    }
+	
+  fbuf1.sputn(str1.data(), str1.size());
+  fbuf1.close();
+
+  wfilebuf fbuf2;
+  fbuf2.pubimbue(loc);
+  fbuf2.open("tmp_9178", std::ios_base::in);
+	
+  wstring str2;
+  copy(istreambuf_iterator<wchar_t>(&fbuf2),
+       istreambuf_iterator<wchar_t>(),
+       back_inserter(str2));
+
+  VERIFY( str1 == str2 );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/9520.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/9520.cc
new file mode 100644
index 000000000..f791b86aa
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/9520.cc
@@ -0,0 +1,61 @@
+// { dg-require-namedlocale "de_DE.ISO-8859-15@euro" }
+
+// 2003-05-03  Petur Runolfsson <peturr02@ru.is>
+
+// Copyright (C) 2003, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <testsuite_hooks.h>
+#include <fstream>
+#include <cstdio>
+
+// libstdc++/9520
+void test01()
+{
+  using namespace std;
+
+  bool test __attribute__((unused)) = true;
+  const char* name = "tmp_9520";
+
+  FILE* file = fopen(name, "w");
+  for (int i = 1; i < 256; ++i)
+    putc(static_cast<unsigned char>(i), file);
+  fclose(file);
+
+  locale loc (locale("de_DE.ISO-8859-15@euro"));
+  wchar_t buf[1];
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.pubsetbuf(buf, 1);
+  fb.open(name, ios_base::in);
+
+  for (int j = 1; j < 256; ++j)
+    {
+      wfilebuf::int_type c1 = fb.sgetc();
+      VERIFY( c1 != wfilebuf::traits_type::eof() );
+      wfilebuf::int_type c2 = fb.sbumpc();
+      VERIFY( c1 == c2 );
+    }
+
+  fb.close();
+}
+
+int main()
+{
+  test01();  
+  return 0;
+}