1 # strsignal.m4 serial 4
2 dnl Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_STRSIGNAL],
9 dnl Persuade glibc <string.h> to declare strsignal().
10 AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
12 AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
13 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
15 AC_CHECK_DECLS_ONCE([strsignal])
16 if test $ac_cv_have_decl_strsignal = no; then
20 AC_CHECK_FUNCS([strsignal])
21 if test $ac_cv_func_strsignal = yes; then
22 dnl Check if strsignal behaves reasonably for out-of-range signal numbers.
23 dnl On Solaris it returns NULL; on AIX 5.1 it returns (char *) -1.
24 AC_CACHE_CHECK([whether strsignal always returns a string],
25 [gl_cv_func_working_strsignal],
29 #include <unistd.h> /* NetBSD 5.0 declares it in wrong header. */
31 [[char *s = strsignal (-1);
32 return !(s != (char *) 0 && s != (char *) -1);]])],
33 [gl_cv_func_working_strsignal=yes],
34 [gl_cv_func_working_strsignal=no],
36 solaris* | aix*) gl_cv_func_working_strsignal=no;;
37 *) gl_cv_func_working_strsignal="guessing yes";;
40 gl_cv_func_working_strsignal=no
43 if test "$gl_cv_func_working_strsignal" = no; then
44 if test $ac_cv_func_strsignal = yes; then
47 AC_LIBOBJ([strsignal])
52 # Prerequisites of lib/strsignal.c.
53 AC_DEFUN([gl_PREREQ_STRSIGNAL], [
54 AC_REQUIRE([AC_DECL_SYS_SIGLIST])
55 AC_CHECK_DECLS([_sys_siglist], [], [], [#include <signal.h>])