mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-01 08:17:38 +00:00
46 lines
1.3 KiB
Plaintext
46 lines
1.3 KiB
Plaintext
# environ.m4 serial 7
|
|
dnl Copyright (C) 2001-2004, 2006-2020 Free Software Foundation, Inc.
|
|
dnl This file is free software; the Free Software Foundation
|
|
dnl gives unlimited permission to copy and/or distribute it,
|
|
dnl with or without modifications, as long as this notice is preserved.
|
|
|
|
AC_DEFUN_ONCE([gl_ENVIRON],
|
|
[
|
|
AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
|
|
dnl Persuade glibc <unistd.h> to declare environ.
|
|
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
|
|
|
|
AC_CHECK_HEADERS_ONCE([unistd.h])
|
|
gt_CHECK_VAR_DECL(
|
|
[#if HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
/* mingw, BeOS, Haiku declare environ in <stdlib.h>, not in <unistd.h>. */
|
|
#include <stdlib.h>
|
|
],
|
|
[environ])
|
|
if test $gt_cv_var_environ_declaration != yes; then
|
|
HAVE_DECL_ENVIRON=0
|
|
fi
|
|
])
|
|
|
|
# Check if a variable is properly declared.
|
|
# gt_CHECK_VAR_DECL(includes,variable)
|
|
AC_DEFUN([gt_CHECK_VAR_DECL],
|
|
[
|
|
define([gt_cv_var], [gt_cv_var_]$2[_declaration])
|
|
AC_CACHE_CHECK([if $2 is properly declared], [gt_cv_var],
|
|
[AC_COMPILE_IFELSE(
|
|
[AC_LANG_PROGRAM(
|
|
[[$1
|
|
extern struct { int foo; } $2;]],
|
|
[[$2.foo = 1;]])],
|
|
[gt_cv_var=no],
|
|
[gt_cv_var=yes])])
|
|
if test $gt_cv_var = yes; then
|
|
AC_DEFINE([HAVE_]m4_translit($2, [a-z], [A-Z])[_DECL], 1,
|
|
[Define if you have the declaration of $2.])
|
|
fi
|
|
undefine([gt_cv_var])
|
|
])
|