subr.rtl/rtl_fetch{_git,}.subr: split.

subr.rtl/rtl_{filepath,complex}.subr: split.
subr.rtl/{rtl_filepath,}.subr: split.
subr.rtl/rtl_{platform,complex}.subr: split.

6 files changed, 315 insertions, 294 deletions

diff --git a/subr.rtl/rtl.subr b/subr.rtl/rtl.subr
index b123555f..532cb514 100644
--- a/subr.rtl/rtl.subr
+++ b/subr.rtl/rtl.subr
@@ -2,7 +2,6 @@
 # set +o errexit -o noglob -o nounset is assumed.
 #
 
-rtl_basename() { local _fname="${1##*/}"; printf "%s" "${_fname}"; };
 rtl_date() { command date "+${1:-${DEFAULT_TIMESTAMP_FMT:-"%Y/%m/%d %H:%M:%S"}}"; };
 rtl_set_IFS_nl() { IFS="
 "; };
diff --git a/subr.rtl/rtl_complex.subr b/subr.rtl/rtl_complex.subr
index 34b87837..8866484f 100644
--- a/subr.rtl/rtl_complex.subr
+++ b/subr.rtl/rtl_complex.subr
@@ -2,88 +2,6 @@
 # set +o errexit -o noglob -o nounset is assumed.
 #
 
-rtl_check_digest() {
-	local _fname="${1}" _digest_check="${2}" _digest=""; RTL_CHECK_DIGEST_DIGEST="";
-	if ! [ -e "${_fname}" ]; then
-		return 1;
-	else	set -- $(sha256sum "${_fname}");
-		RTL_CHECK_DIGEST_DIGEST="${1}";
-		if [ "${RTL_CHECK_DIGEST_DIGEST}" = "${_digest_check}" ]; then
-			return 0;
-		else
-			return 1;
-		fi;
-	fi;
-};
-
-rtl_check_digest_file() {
-	local _fname="${1}" _digest_check="${2}" _digest_fname="${3}" _digest="" RTL_CHECK_DIGEST_DIGEST="";
-	if !  [ -e "${_digest_fname}" ]; then
-		return 1;
-	else	_digest="$(cat "${_digest_fname}")";
-		if [ "${_digest}" != "${_digest_check}" ]\
-		|| ! rtl_check_digest "${_fname}" "${_digest_check}"; then
-			return 1;
-		fi;
-	fi;
-};
-
-rtl_check_path_vars() {
-	local _vnames="${1}" _rc=0 _vname="" _vname_val=""; _status="";
-	for _vname in ${_vnames}; do
-		_vname_val="$(rtl_get_var_unsafe "${_vname}")";
-		if [ -z "${_vname_val}" ]; then
-			_rc=1; _status="Error: variable \`${_vname}' is empty or unset."; break;
-		elif [ "${_vname_val#* *}" != "${_vname_val}" ]; then
-			_rc=2; _status="Error: variable \`${_vname}' contains one or more whitespace characters."; break;
-		fi;
-	done;
-	return "${_rc}";
-};
-
-rtl_check_prereqs() {
-	local _cmd="" _cmds_missing="" _rc=0; _status="";
-	for _cmd in "${@}"; do
-		if ! which "${_cmd}" >/dev/null 2>&1; then
-			_cmds_missing="${_cmds_missing:+${_cmds_missing} }${_cmd}";
-		fi;
-	done;
-	if [ -n "${_cmds_missing}" ]; then
-		_rc=1; _status="Error: missing prerequisite package(s): ${_cmds_missing}";
-	fi;
-	return "${_rc}";
-};
-
-rtl_clean_env() {
-	local _env_vars_except="${1}" _env_var="" _env_vars="";
-	_env_vars="$(export | sed -ne '/^export/{s/^export //;s/=.*$//p}')";
-	for _env_var in ${_env_vars}; do
-		if [ "${_env_var#DEFAULT_}" != "${_env_var}" ]\
-		|| [ "${_env_var#PKG_}" != "${_env_var}" ]; then
-			_env_vars_except="$(rtl_lconcat "${_env_vars_except}" "${_env_var}")";
-		fi;
-	done;
-	rtl_unset_vars $(rtl_lfilter "${_env_vars}" "${_env_vars_except}");
-};
-
-rtl_dirname() {
-	local _dname="${1%/*}";
-	while rtl_matchr "${_dname}" "*/"; do
-		_dname="${_dname%/}";
-	done; printf "%s" "${_dname:-/}";
-};
-
-rtl_exists_any() {
-	local _subdir="${1}"; shift;
-	while [ "${#}" -gt 0 ]; do
-		if [ -e "${_subdir}/${1}" ]; then
-			return 0;
-		else
-			shift;
-		fi;
-	done; return 1;
-};
-
 rtl_export_vars() {
 	local _unsetfl=0; [ "x${1}" = "x-u" ] && { _unsetfl=1; shift; };
 	while [ "${#}" -ge 2 ]; do
@@ -135,49 +53,6 @@ rtl_filter_vars() {
 	printf "%s" "${_vars}";
 };
 
-rtl_flock_acquire() {
-	local _fd="${1}" _conflict_exit_code="${2:-253}" _wait="${3:-3600}"
-	while true; do
-		if flock -E "${_conflict_exit_code}" -w "${_wait}" "${_fd}"; then
-			break;
-		elif [ "${?}" -eq "${_conflict_exit_code}" ]; then
-			continue;
-		else
-			return "${?}";
-		fi;
-	done;
-};
-
-rtl_get_cpu_count() {
-	local _line="" _ncpus=0 _rc=0 _sname="$(uname -s 2>/dev/null)"; _status="";
-	case "${_sname}" in
-	Linux)	if [ ! -e "/proc/cpuinfo" ]; then
-			_rc=1; _status="Error: /proc/cpuinfo non-existent.";
-		else	while read -r _line; do
-				if rtl_match "${_line}" "processor*:"; then
-					: $((_ncpus+=1));
-				fi;
-			done < /proc/cpuinfo; printf "%s" "${_ncpus}";
-		fi; ;;
-	*)	_rc=1; _status="Error: unknown platform \`${_sname}'."; ;;
-	esac; return "${_rc}";
-};
-
-rtl_get_var_unsafe() {
-	local _vname="";
-	if [ "x${1}" = "x-u" ]; then
-		shift; _vname="$(rtl_toupper "${1}")";
-	else
-		_vname="${1}";
-	fi;
-	eval echo \${${_vname}} 2>/dev/null;
-};
-
-rtl_get_vars_fast() {
-	local _pattern="${1}";
-	set | awk -F= '/'"${_pattern}"'/{print $1}' | sort;
-};
-
 rtl_head() {
 	local _pattern="${1}" _s="${2}";
 	while true; do
@@ -190,34 +65,6 @@ rtl_head() {
 	printf "%s" "${_s}";
 };
 
-rtl_is_newer() {
-	local _new_fname="${1}" _old_fname="${2}" _new_ts="" _old_ts="";
-	if ! [ -e "${_old_fname}" ]; then
-		return 0;
-	else	_new_ts="$(stat -c %Y "${_new_fname}" 2>&1)";
-		_old_ts="$(stat -c %Y "${_old_fname}" 2>&1)";
-		if [ "${_new_ts:-0}" -gt "${_old_ts:-0}" ]; then
-			return 0;
-		else
-			return 1;
-		fi;
-	fi;
-};
-
-rtl_kill_tree() {
-	local _pid="${1}" _signal="${2:-TERM}" _pid_child="" _pids="";
-	if _pids="$(pgrep -P "${_pid}")"\
-	&& [ -n "${_pids}" ]; then
-		for _pid_child in ${_pids}; do
-			rtl_kill_tree "${_pid_child}" "${_signal}";
-		done;
-	fi;
-	if [ "${_pid:-0}" -ne "${$}" ]\
-	&& kill "-${_signal}" "${_pid}" 2>/dev/null; then
-		RTL_KILL_TREE_PIDS="$(rtl_lconcat "${RTL_KILL_TREE_PIDS}" "${_pid}")";
-	fi;
-};
-
 rtl_percentage() {
 	local _in="${1}" _max="${2}" _perc;
 	_perc="$((100 * ${_in} + ${_max} / 2))";
@@ -225,54 +72,4 @@ rtl_percentage() {
 	printf "%d\n" "${_perc}";
 };
 
-rtl_prompt() {
-	local _fmt="${1}" _choice=""; shift;
-	printf "${_fmt}? (y|N) " "${@}";
-	read -r _choice;
-	case "${_choice}" in
-	[yY])	_choice=1; ;;
-	*)	_choice=0; ;;
-	esac;
-	return "${_choice}";
-};
-
-rtl_rc() {
-	local _nflag="${1}" _cmd="${2}"; shift 2;
-	case "${_nflag}" in
-	1)	     if [ "${#}" -gt 0 ]; then
-			rtl_log_msg notice "Command line: %s %s" "${_cmd}" "${*}";
-		else
-			rtl_log_msg notice "Command line: %s" "${_cmd}";
-		fi; ;;
-	*)	"${_cmd}" "${@}";
-	esac;
-};
-
-rtl_run_cmd_unsplit() {
-	local _cmd="${1}" _cmdline="" _rc="" IFS; shift;
-	while [ ${#} -gt 0 ]; do
-		[ -n "${1}" ] &&\
-			_cmdline="${_cmdline:+${_cmdline}:}${1}";
-		shift;
-	done;
-	IFS=:; ${_cmd} ${_cmdline}; _rc=$?;
-	return ${_rc};
-};
-
-rtl_set_vars() {
-	local	_vars_set_vname="${1}" _vname_dst="${2}" _vname_src_tmpls="${3}"	\
-		_vars_set_old="" _vars_set_tmp="" _vname_src="";
-	for _vname_src in $(rtl_toupper "${_vname_src_tmpls}"); do
-		_vname_src="${_vname_src}_${_vname_dst}";
-		_vval_src="$(rtl_get_var_unsafe "${_vname_src}")";
-		if [ -n "${_vval_src}" ]; then
-			rtl_set_var_unsafe "PKG_${_vname_dst}" "${_vval_src}";
-			_vars_set_tmp="$(rtl_lconcat "${_vars_set_tmp}" "PKG_${_vname_dst}")";
-		fi;
-	done;
-	_vars_set_old="$(rtl_get_var_unsafe "${_vars_set_vname}")";
-	rtl_set_var_unsafe "${_vars_set_vname}"					\
-		"$(rtl_lconcat "${_vars_set_old}" "${_vars_set_tmp}")";
-};
-
 # vim:filetype=sh
diff --git a/subr.rtl/rtl_fetch.subr b/subr.rtl/rtl_fetch.subr
index f5410e30..c8e12d1b 100644
--- a/subr.rtl/rtl_fetch.subr
+++ b/subr.rtl/rtl_fetch.subr
@@ -2,96 +2,6 @@
 # set +o errexit -o noglob -o nounset is assumed.
 #
 
-rtl_fetch_mirror_urls_git() {
-	local _git_args="${1}" _tgtdir="${2}" _rc=0 _repo_dname="" _subdir="" _url="" _url_spec=""; shift 2;
-
-	for _url_spec in "${@}"; do
-		_subdir="${_url_spec%=*}"; _subdir="${_subdir##*/}"; _url="${_url_spec#*=}"; _url="${_url%@*}";
-		_repo_dname="${_url##*/}"; [ "${_repo_dname%.git}" = "${_repo_dname}" ] && _repo_dname="${_repo_dname}.git";
-
-		if [ ! -e "$(rtl_dirname "${_tgtdir}")" ]; then
-			rtl_fileop mkdir "$(rtl_dirname "${_tgtdir}")";
-		fi;
-		(set -o errexit -o noglob -o nounset;
-		rtl_flock_acquire 4 || exit "${?}";
-		trap "rm -f \"${_tgtdir}/.fetching\"" EXIT;
-		if [ -e "${_tgtdir}/${_repo_dname}" ]; then
-			(rtl_fileop cd "${_tgtdir}/${_repo_dname}" && git fetch ${_git_args} --all) || return 1;
-		else	(rtl_fileop cd "${_tgtdir}" && git clone ${_git_args} --mirror "${_url}") || return 1;
-		fi) 4<>"${_tgtdir}/.fetching";
-		if [ "${?}" -ne 0 ]; then
-			_rc=1;
-		fi;
-	done; return "${_rc}";
-};
-
-rtlp_fetch_url_git() {
-	local	_cache_dname="${1}" _git_args="${2}" _git_branch="${3}" _mirrors="${4}" _pkg_name="${5}"\
-		_subdir="${6}" _tgtdir="${7}" _url="${8}" _cache_dname_full="" _clonefl=0 _oldpwd="" _url_base="";
-
-	_cache_dname_full="${_cache_dname}/${_subdir##*/}";
-	(set -o errexit -o noglob -o nounset;
-	rtl_flock_acquire 4 || exit "${?}";
-	trap "rm -f \"${_cache_dname_full%%[/]}.fetching\"" EXIT;
-	if [ -e "${_cache_dname_full}" ]; then
-		(rtl_fileop cd "${_cache_dname_full}" &&\
-			git pull ${_git_args} origin "${_git_branch:-main}") || return 1;
-		(rtl_fileop cd "${_cache_dname_full}" &&\
-			git submodule update) || return 1;
-	else	if git clone ${_git_args} -b "${_git_branch:-main}" "${_url}" "${_cache_dname_full}"; then
-			_clonefl=1;
-		elif [ "${_mirrors}" = "skip" ]; then
-			return 1;
-		else	for _url_base in ${_mirrors}; do
-				if git clone ${_git_args} -b "${_git_branch:-main}" "${_url_base}/${_pkg_name}/${_url##*/}" "${_cache_dname_full}"; then
-					_clonefl=1; break;
-				fi;
-			done;
-		fi;
-		if [ "${_clonefl}" -eq 0 ]; then
-			return 1;
-		else	if [ -n "${_git_branch}" ]; then
-				(rtl_fileop cd "${_cache_dname_full}" &&\
-					git checkout "${_git_branch}") || return 1;
-			fi;
-			(rtl_fileop cd "${_cache_dname_full}" &&\
-				git submodule update --init) || return 1;
-		fi;
-	fi;
-	if [ "${_cache_dname}" != "${_tgtdir}" ]; then
-		_oldpwd="${PWD}"; rtl_fileop cd "${_tgtdir}" || return 1;
-		rtl_fileop rm "${_tgtdir}/${_subdir}" || return 1;
-		if [ ! -e "$(rtl_dirname "${_tgtdir}/${_subdir}")" ]; then
-			rtl_fileop mkdir "$(rtl_dirname "${_tgtdir}/${_subdir}")";
-		fi;
-		rtl_fileop cp "${_cache_dname_full}" "${_tgtdir}/${_subdir}" || return 1;
-		rtl_fileop cd "${_oldpwd}" || return 1;
-	fi) 4<>"${_cache_dname_full%%[/]}.fetching";
-
-	if [ "${?}" -eq 0 ]; then
-		cd "$(pwd)";
-	else
-		return 1;
-	fi;
-};
-
-rtl_fetch_urls_git() {
-	local	_cache_dname="${1}" _git_args="${2}" _tgtdir="${3}" _pkg_name="${4}" _mirrors="${5}"\
-		_git_branch="" _subdir="" _url="" _url_spec=""; shift 5;
-
-	for _url_spec in "${@}"; do
-		_subdir="${_url_spec%=*}"; _url="${_url_spec#*=}"; _url="${_url%@*}";
-		if [ "${_url_spec#*@}" != "${_url_spec}" ]; then
-			_git_branch=${_url_spec#*@};
-		fi;
-		if ! rtlp_fetch_url_git	\
-				"${_cache_dname}" "${_git_args}" "${_git_branch}" "${_mirrors}"\
-				"${_pkg_name}" "${_subdir}" "${_tgtdir}" "${_url}"; then
-			return 1;
-		fi;
-	done;
-};
-
 # N.B.	URLs ($1) may contain `?' or '&' characters.
 rtl_fetch_url_wget() {
 	local _urls="${1}" _sha256sum_src="${2}" _target_dname="${3}" _target_fname="${4}" _target_name="${5}" _mirrors="${6:-}"\
diff --git a/subr.rtl/rtl_fetch_git.subr b/subr.rtl/rtl_fetch_git.subr
new file mode 100644
index 00000000..2d6ce8ab
--- /dev/null
+++ b/subr.rtl/rtl_fetch_git.subr
@@ -0,0 +1,95 @@
+#
+# set +o errexit -o noglob -o nounset is assumed.
+#
+
+rtlp_fetch_url_git() {
+	local	_cache_dname="${1}" _git_args="${2}" _git_branch="${3}" _mirrors="${4}" _pkg_name="${5}"\
+		_subdir="${6}" _tgtdir="${7}" _url="${8}" _cache_dname_full="" _clonefl=0 _oldpwd="" _url_base="";
+
+	_cache_dname_full="${_cache_dname}/${_subdir##*/}";
+	(set -o errexit -o noglob -o nounset;
+	rtl_flock_acquire 4 || exit "${?}";
+	trap "rm -f \"${_cache_dname_full%%[/]}.fetching\"" EXIT;
+	if [ -e "${_cache_dname_full}" ]; then
+		(rtl_fileop cd "${_cache_dname_full}" &&\
+			git pull ${_git_args} origin "${_git_branch:-main}") || return 1;
+		(rtl_fileop cd "${_cache_dname_full}" &&\
+			git submodule update) || return 1;
+	else	if git clone ${_git_args} -b "${_git_branch:-main}" "${_url}" "${_cache_dname_full}"; then
+			_clonefl=1;
+		elif [ "${_mirrors}" = "skip" ]; then
+			return 1;
+		else	for _url_base in ${_mirrors}; do
+				if git clone ${_git_args} -b "${_git_branch:-main}" "${_url_base}/${_pkg_name}/${_url##*/}" "${_cache_dname_full}"; then
+					_clonefl=1; break;
+				fi;
+			done;
+		fi;
+		if [ "${_clonefl}" -eq 0 ]; then
+			return 1;
+		else	if [ -n "${_git_branch}" ]; then
+				(rtl_fileop cd "${_cache_dname_full}" &&\
+					git checkout "${_git_branch}") || return 1;
+			fi;
+			(rtl_fileop cd "${_cache_dname_full}" &&\
+				git submodule update --init) || return 1;
+		fi;
+	fi;
+	if [ "${_cache_dname}" != "${_tgtdir}" ]; then
+		_oldpwd="${PWD}"; rtl_fileop cd "${_tgtdir}" || return 1;
+		rtl_fileop rm "${_tgtdir}/${_subdir}" || return 1;
+		if [ ! -e "$(rtl_dirname "${_tgtdir}/${_subdir}")" ]; then
+			rtl_fileop mkdir "$(rtl_dirname "${_tgtdir}/${_subdir}")";
+		fi;
+		rtl_fileop cp "${_cache_dname_full}" "${_tgtdir}/${_subdir}" || return 1;
+		rtl_fileop cd "${_oldpwd}" || return 1;
+	fi) 4<>"${_cache_dname_full%%[/]}.fetching";
+
+	if [ "${?}" -eq 0 ]; then
+		cd "$(pwd)";
+	else
+		return 1;
+	fi;
+};
+
+rtl_fetch_mirror_urls_git() {
+	local _git_args="${1}" _tgtdir="${2}" _rc=0 _repo_dname="" _subdir="" _url="" _url_spec=""; shift 2;
+
+	for _url_spec in "${@}"; do
+		_subdir="${_url_spec%=*}"; _subdir="${_subdir##*/}"; _url="${_url_spec#*=}"; _url="${_url%@*}";
+		_repo_dname="${_url##*/}"; [ "${_repo_dname%.git}" = "${_repo_dname}" ] && _repo_dname="${_repo_dname}.git";
+
+		if [ ! -e "$(rtl_dirname "${_tgtdir}")" ]; then
+			rtl_fileop mkdir "$(rtl_dirname "${_tgtdir}")";
+		fi;
+		(set -o errexit -o noglob -o nounset;
+		rtl_flock_acquire 4 || exit "${?}";
+		trap "rm -f \"${_tgtdir}/.fetching\"" EXIT;
+		if [ -e "${_tgtdir}/${_repo_dname}" ]; then
+			(rtl_fileop cd "${_tgtdir}/${_repo_dname}" && git fetch ${_git_args} --all) || return 1;
+		else	(rtl_fileop cd "${_tgtdir}" && git clone ${_git_args} --mirror "${_url}") || return 1;
+		fi) 4<>"${_tgtdir}/.fetching";
+		if [ "${?}" -ne 0 ]; then
+			_rc=1;
+		fi;
+	done; return "${_rc}";
+};
+
+rtl_fetch_urls_git() {
+	local	_cache_dname="${1}" _git_args="${2}" _tgtdir="${3}" _pkg_name="${4}" _mirrors="${5}"\
+		_git_branch="" _subdir="" _url="" _url_spec=""; shift 5;
+
+	for _url_spec in "${@}"; do
+		_subdir="${_url_spec%=*}"; _url="${_url_spec#*=}"; _url="${_url%@*}";
+		if [ "${_url_spec#*@}" != "${_url_spec}" ]; then
+			_git_branch=${_url_spec#*@};
+		fi;
+		if ! rtlp_fetch_url_git	\
+				"${_cache_dname}" "${_git_args}" "${_git_branch}" "${_mirrors}"\
+				"${_pkg_name}" "${_subdir}" "${_tgtdir}" "${_url}"; then
+			return 1;
+		fi;
+	done;
+};
+
+# vim:filetype=sh
diff --git a/subr.rtl/rtl_filepath.subr b/subr.rtl/rtl_filepath.subr
new file mode 100644
index 00000000..fa1baf57
--- /dev/null
+++ b/subr.rtl/rtl_filepath.subr
@@ -0,0 +1,96 @@
+#
+# set +o errexit -o noglob -o nounset is assumed.
+#
+
+rtl_basename() {
+	local _fname="${1##*/}"; printf "%s" "${_fname}";
+};
+
+rtl_check_digest() {
+	local _fname="${1}" _digest_check="${2}" _digest=""; RTL_CHECK_DIGEST_DIGEST="";
+	if ! [ -e "${_fname}" ]; then
+		return 1;
+	else	set -- $(sha256sum "${_fname}");
+		RTL_CHECK_DIGEST_DIGEST="${1}";
+		if [ "${RTL_CHECK_DIGEST_DIGEST}" = "${_digest_check}" ]; then
+			return 0;
+		else
+			return 1;
+		fi;
+	fi;
+};
+
+rtl_check_digest_file() {
+	local _fname="${1}" _digest_check="${2}" _digest_fname="${3}" _digest="" RTL_CHECK_DIGEST_DIGEST="";
+	if !  [ -e "${_digest_fname}" ]; then
+		return 1;
+	else	_digest="$(cat "${_digest_fname}")";
+		if [ "${_digest}" != "${_digest_check}" ]\
+		|| ! rtl_check_digest "${_fname}" "${_digest_check}"; then
+			return 1;
+		fi;
+	fi;
+};
+
+rtl_check_path_vars() {
+	local _vnames="${1}" _rc=0 _vname="" _vname_val=""; _status="";
+	for _vname in ${_vnames}; do
+		_vname_val="$(rtl_get_var_unsafe "${_vname}")";
+		if [ -z "${_vname_val}" ]; then
+			_rc=1; _status="Error: variable \`${_vname}' is empty or unset."; break;
+		elif [ "${_vname_val#* *}" != "${_vname_val}" ]; then
+			_rc=2; _status="Error: variable \`${_vname}' contains one or more whitespace characters."; break;
+		fi;
+	done;
+	return "${_rc}";
+};
+
+rtl_dirname() {
+	local _dname="${1%/*}";
+	case "${_dname}" in
+	"")	_dname="."; ;;
+	*)	while rtl_matchr "${_dname}" "*/"; do
+			_dname="${_dname%/}";
+		done; ;;
+	esac; printf "%s" "${_dname:-/}";
+};
+
+rtl_exists_any() {
+	local _subdir="${1}"; shift;
+	while [ "${#}" -gt 0 ]; do
+		if [ -e "${_subdir}/${1}" ]; then
+			return 0;
+		else
+			shift;
+		fi;
+	done; return 1;
+};
+
+rtl_flock_acquire() {
+	local _fd="${1}" _conflict_exit_code="${2:-253}" _wait="${3:-3600}"
+	while true; do
+		if flock -E "${_conflict_exit_code}" -w "${_wait}" "${_fd}"; then
+			break;
+		elif [ "${?}" -eq "${_conflict_exit_code}" ]; then
+			continue;
+		else
+			return "${?}";
+		fi;
+	done;
+};
+
+rtl_is_newer() {
+	local _new_fname="${1}" _old_fname="${2}" _new_ts="" _old_ts="";
+	if ! [ -e "${_old_fname}" ]; then
+		return 0;
+	else	_new_ts="$(stat -c %Y "${_new_fname}" 2>&1)";
+		_old_ts="$(stat -c %Y "${_old_fname}" 2>&1)";
+		if [ "${_new_ts:-0}" -gt "${_old_ts:-0}" ]; then
+			return 0;
+		else
+			return 1;
+		fi;
+	fi;
+};
+
+# vim:filetype=sh
diff --git a/subr.rtl/rtl_platform.subr b/subr.rtl/rtl_platform.subr
new file mode 100644
index 00000000..c8137e56
--- /dev/null
+++ b/subr.rtl/rtl_platform.subr
@@ -0,0 +1,124 @@
+#
+# set +o errexit -o noglob -o nounset is assumed.
+#
+
+rtl_check_prereqs() {
+	local _cmd="" _cmds_missing="" _rc=0; _status="";
+	for _cmd in "${@}"; do
+		if ! which "${_cmd}" >/dev/null 2>&1; then
+			_cmds_missing="${_cmds_missing:+${_cmds_missing} }${_cmd}";
+		fi;
+	done;
+	if [ -n "${_cmds_missing}" ]; then
+		_rc=1; _status="Error: missing prerequisite package(s): ${_cmds_missing}";
+	fi;
+	return "${_rc}";
+};
+
+rtl_clean_env() {
+	local _env_vars_except="${1}" _env_var="" _env_vars="";
+	_env_vars="$(export | sed -ne '/^export/{s/^export //;s/=.*$//p}')";
+	for _env_var in ${_env_vars}; do
+		if [ "${_env_var#DEFAULT_}" != "${_env_var}" ]\
+		|| [ "${_env_var#PKG_}" != "${_env_var}" ]; then
+			_env_vars_except="$(rtl_lconcat "${_env_vars_except}" "${_env_var}")";
+		fi;
+	done;
+	rtl_unset_vars $(rtl_lfilter "${_env_vars}" "${_env_vars_except}");
+};
+
+rtl_get_cpu_count() {
+	local _line="" _ncpus=0 _rc=0 _sname="$(uname -s 2>/dev/null)"; _status="";
+	case "${_sname}" in
+	Linux)	if [ ! -e "/proc/cpuinfo" ]; then
+			_rc=1; _status="Error: /proc/cpuinfo non-existent.";
+		else	while read -r _line; do
+				if rtl_match "${_line}" "processor*:"; then
+					: $((_ncpus+=1));
+				fi;
+			done < /proc/cpuinfo; printf "%s" "${_ncpus}";
+		fi; ;;
+	*)	_rc=1; _status="Error: unknown platform \`${_sname}'."; ;;
+	esac; return "${_rc}";
+};
+
+rtl_get_var_unsafe() {
+	local _vname="";
+	if [ "x${1}" = "x-u" ]; then
+		shift; _vname="$(rtl_toupper "${1}")";
+	else
+		_vname="${1}";
+	fi;
+	eval echo \${${_vname}} 2>/dev/null;
+};
+
+rtl_get_vars_fast() {
+	local _pattern="${1}";
+	set | awk -F= '/'"${_pattern}"'/{print $1}' | sort;
+};
+
+rtl_kill_tree() {
+	local _pid="${1}" _signal="${2:-TERM}" _pid_child="" _pids="";
+	if _pids="$(pgrep -P "${_pid}")"\
+	&& [ -n "${_pids}" ]; then
+		for _pid_child in ${_pids}; do
+			rtl_kill_tree "${_pid_child}" "${_signal}";
+		done;
+	fi;
+	if [ "${_pid:-0}" -ne "${$}" ]\
+	&& kill "-${_signal}" "${_pid}" 2>/dev/null; then
+		RTL_KILL_TREE_PIDS="$(rtl_lconcat "${RTL_KILL_TREE_PIDS}" "${_pid}")";
+	fi;
+};
+
+rtl_prompt() {
+	local _fmt="${1}" _choice=""; shift;
+	printf "${_fmt}? (y|N) " "${@}";
+	read -r _choice;
+	case "${_choice}" in
+	[yY])	_choice=1; ;;
+	*)	_choice=0; ;;
+	esac;
+	return "${_choice}";
+};
+
+rtl_rc() {
+	local _nflag="${1}" _cmd="${2}"; shift 2;
+	case "${_nflag}" in
+	1)	     if [ "${#}" -gt 0 ]; then
+			rtl_log_msg notice "Command line: %s %s" "${_cmd}" "${*}";
+		else
+			rtl_log_msg notice "Command line: %s" "${_cmd}";
+		fi; ;;
+	*)	"${_cmd}" "${@}";
+	esac;
+};
+
+rtl_run_cmd_unsplit() {
+	local _cmd="${1}" _cmdline="" _rc="" IFS; shift;
+	while [ ${#} -gt 0 ]; do
+		[ -n "${1}" ] &&\
+			_cmdline="${_cmdline:+${_cmdline}:}${1}";
+		shift;
+	done;
+	IFS=:; ${_cmd} ${_cmdline}; _rc=$?;
+	return ${_rc};
+};
+
+rtl_set_vars() {
+	local	_vars_set_vname="${1}" _vname_dst="${2}" _vname_src_tmpls="${3}"	\
+		_vars_set_old="" _vars_set_tmp="" _vname_src="";
+	for _vname_src in $(rtl_toupper "${_vname_src_tmpls}"); do
+		_vname_src="${_vname_src}_${_vname_dst}";
+		_vval_src="$(rtl_get_var_unsafe "${_vname_src}")";
+		if [ -n "${_vval_src}" ]; then
+			rtl_set_var_unsafe "PKG_${_vname_dst}" "${_vval_src}";
+			_vars_set_tmp="$(rtl_lconcat "${_vars_set_tmp}" "PKG_${_vname_dst}")";
+		fi;
+	done;
+	_vars_set_old="$(rtl_get_var_unsafe "${_vars_set_vname}")";
+	rtl_set_var_unsafe "${_vars_set_vname}"					\
+		"$(rtl_lconcat "${_vars_set_old}" "${_vars_set_tmp}")";
+};
+
+# vim:filetype=sh