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| -rw-r--r-- | m4/setenv.m4 | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/m4/setenv.m4 b/m4/setenv.m4 new file mode 100644 index 000000000..88d5e4c20 --- /dev/null +++ b/m4/setenv.m4 @@ -0,0 +1,72 @@ +# setenv.m4 serial 5 +dnl Copyright (C) 2001-2004 Free Software Foundation, Inc. +dnl This file is free software, distributed under the terms of the GNU +dnl General Public License. As a special exception to the GNU General +dnl Public License, this file may be distributed as part of a program +dnl that contains a configuration script generated by Autoconf, under +dnl the same distribution terms as the rest of that program. + +AC_DEFUN([gt_FUNC_SETENV], +[ + AC_REPLACE_FUNCS(setenv unsetenv) + if test $ac_cv_func_setenv = no; then + gl_PREREQ_SETENV + fi + if test $ac_cv_func_unsetenv = no; then + gl_PREREQ_UNSETENV + else + AC_CACHE_CHECK([for unsetenv() return type], gt_cv_func_unsetenv_ret, + [AC_TRY_COMPILE([#include <stdlib.h> +extern +#ifdef __cplusplus +"C" +#endif +#if defined(__STDC__) || defined(__cplusplus) +int unsetenv (const char *name); +#else +int unsetenv(); +#endif +], , gt_cv_func_unsetenv_ret='int', gt_cv_func_unsetenv_ret='void')]) + if test $gt_cv_func_unsetenv_ret = 'void'; then + AC_DEFINE(VOID_UNSETENV, 1, [Define if unsetenv() returns void, not int.]) + fi + 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_MSG_CHECKING([if $2 is properly declared]) + AC_CACHE_VAL(gt_cv_var, [ + AC_TRY_COMPILE([$1 + extern struct { int foo; } $2;], + [$2.foo = 1;], + gt_cv_var=no, + gt_cv_var=yes)]) + AC_MSG_RESULT($gt_cv_var) + if test $gt_cv_var = yes; then + AC_DEFINE([HAVE_]translit($2, [a-z], [A-Z])[_DECL], 1, + [Define if you have the declaration of $2.]) + fi +]) + +# Prerequisites of lib/setenv.c. +AC_DEFUN([gl_PREREQ_SETENV], +[ + AC_REQUIRE([AC_FUNC_ALLOCA]) + AC_CHECK_HEADERS_ONCE(unistd.h) + AC_CHECK_HEADERS(search.h) + AC_CHECK_FUNCS(tsearch) + gt_CHECK_VAR_DECL([#include <errno.h>], errno) + gt_CHECK_VAR_DECL([#include <unistd.h>], environ) +]) + +# Prerequisites of lib/unsetenv.c. +AC_DEFUN([gl_PREREQ_UNSETENV], +[ + AC_CHECK_HEADERS_ONCE(unistd.h) + gt_CHECK_VAR_DECL([#include <errno.h>], errno) + gt_CHECK_VAR_DECL([#include <unistd.h>], environ) +]) |