1 # strerror.m4 serial 12
2 dnl Copyright (C) 2002, 2007-2011 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_STRERROR],
9 AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
10 AC_REQUIRE([gl_HEADER_ERRNO_H])
11 if test -z "$ERRNO_H"; then
12 AC_CACHE_CHECK([for working strerror function],
13 [gl_cv_func_working_strerror],
20 if (!*strerror (-2)) result |= 1;
22 if (!*strerror (0)) result |= 2;
23 if (errno) result |= 4;
25 [gl_cv_func_working_strerror=yes],
26 [gl_cv_func_working_strerror=no],
27 [dnl Be pessimistic on cross-compiles for now.
28 gl_cv_func_working_strerror=no])
30 if test $gl_cv_func_working_strerror = no; then
31 dnl The system's strerror() fails to return a string for out-of-range
32 dnl integers. Replace it.
36 dnl The system's strerror() cannot know about the new errno values we add
37 dnl to <errno.h>. Replace it.
42 # Prerequisites of lib/strerror.c.
43 AC_DEFUN([gl_PREREQ_STRERROR], [
44 AC_CHECK_DECLS([strerror])
45 AC_CHECK_HEADERS_ONCE([sys/socket.h])
46 if test $ac_cv_header_sys_socket_h != yes; then
47 dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make
48 dnl the check for those headers unconditional; yet cygwin reports
49 dnl that the headers are present but cannot be compiled (since on
50 dnl cygwin, all socket information should come from sys/socket.h).
51 AC_CHECK_HEADERS([winsock2.h])