New module sigaction, for mingw.

* modules/sigaction: New module...
* modules/sigaction-tests: ...and its test.
* m4/sigaction.m4: New file.
* lib/sigaction.c: Likewise.
* tests/test-sigaction.c: Likewise.
* m4/signal_h.m4 (gl_SIGNAL_H_DEFAULTS): Add sigaction variables.
* modules/signal (Makefile.am): Likewise.
* lib/signal.in.h (!@HAVE_SIGACTION@): Define replacements when
needed.
* doc/posix-headers/signal.texi (signal.h): Mention provided
types.
* doc/posix-functions/siginterrupt.texi (siginterrupt): Mention
that sigaction is preferable.
* doc/posix-functions/sigaction.texi (sigaction): Mention new
module.
* MODULES.html.sh (Support for systems lacking POSIX:2001): Add
sigaction.

Signed-off-by: Eric Blake <ebb9@byu.net>

1 files changed, 13 insertions, 1 deletions

diff --git a/doc/posix-headers/signal.texi b/doc/posix-headers/signal.texi
index 272e646635..cb4f580e89 100644
--- a/doc/posix-headers/signal.texi
+++ b/doc/posix-headers/signal.texi
@@ -3,12 +3,24 @@
 
 POSIX specification: @url{http://www.opengroup.org/susv3xbd/signal.h.html}
 
-Gnulib module: ---
+Gnulib module: signal
 
 Portability problems fixed by Gnulib:
 @itemize
+@item
+@code{sigset_t} is only declared in <sys/types.h> on some platforms:
+mingw.
+
+@item
+@code{struct sigaction} and @code{siginfo_t} are missing on some
+platforms:
+mingw.
 @end itemize
 
 Portability problems not fixed by Gnulib:
 @itemize
+@item
+@code{struct sigaction} lacks the @code{sa_sigaction} member on some
+platforms; this can also be detected by whether @code{SA_SIGINFO} is defined:
+Interix 3.5.
 @end itemize