Implements extended -r syntax.

build.sh:buildp_ast(): only reset package build step state if ${ARG_RESET_PKG} is 1.
etc/{build.usage,README.md}: updated.
etc/build.usage.short, subr/build_init.subr: implement short help screen.
midipix.env: correctly escape multi-line variable assignment expressions.
subr.rtl/rtl_list.subr: updated.
subr.rtl/rtl_state.subr:rtl_state_set(): correctly implement invalidation.
subr.rtl/rtl_state.subr:rtl_state_test(): honour `LAST'.
subr/build_init.subr:buildp_init_getopts(): implements --reset-pkg.
subr/build_init.subr:buildp_{expand_restart_{at,recursive},process_restart_spec}(): initial implementation.
subr/ex_pkg_{dispatch,env}.subr: updated.
subr/ex_pkg_exec.subr:ex_pkg_exec(): honour `ALL' and `LAST'.
vars/gcc.vars: updated.

1 files changed, 2 insertions, 1 deletions

diff --git a/build.sh b/build.sh
index ba06c3e4..aa4b4b59 100755
--- a/build.sh
+++ b/build.sh
@@ -20,7 +20,8 @@ buildp_ast() {
 	if [ -n "${_pids}" ]; then
 		rtl_log_msg notice "Killed PID(s): %s" "$(rtl_uniq ${_pids})";
 	fi;
-	if [ -n "${EX_PKG_DISPATCH_WAIT}" ]; then
+	if [ -n "${EX_PKG_DISPATCH_WAIT}" ]\
+	&& [ "${ARG_RESET_PKG}" -eq 1 ]; then
 		for _pkg_name in ${EX_PKG_DISPATCH_WAIT}; do
 			rtl_state_clear "${BUILD_WORKDIR}" "${_pkg_name}";
 		done;