1# setenv.m4 serial 6 2dnl Copyright (C) 2001-2004, 2006 Free Software Foundation, Inc. 3dnl This file is free software; the Free Software Foundation 4dnl gives unlimited permission to copy and/or distribute it, 5dnl with or without modifications, as long as this notice is preserved. 6 7AC_DEFUN([gt_FUNC_SETENV], 8[ 9 AC_REPLACE_FUNCS(setenv unsetenv) 10 if test $ac_cv_func_setenv = no; then 11 gl_PREREQ_SETENV 12 fi 13 if test $ac_cv_func_unsetenv = no; then 14 gl_PREREQ_UNSETENV 15 else 16 AC_CACHE_CHECK([for unsetenv() return type], gt_cv_func_unsetenv_ret, 17 [AC_TRY_COMPILE([#include <stdlib.h> 18extern 19#ifdef __cplusplus 20"C" 21#endif 22#if defined(__STDC__) || defined(__cplusplus) 23int unsetenv (const char *name); 24#else 25int unsetenv(); 26#endif 27], , gt_cv_func_unsetenv_ret='int', gt_cv_func_unsetenv_ret='void')]) 28 if test $gt_cv_func_unsetenv_ret = 'void'; then 29 AC_DEFINE(VOID_UNSETENV, 1, [Define if unsetenv() returns void, not int.]) 30 fi 31 fi 32]) 33 34# Check if a variable is properly declared. 35# gt_CHECK_VAR_DECL(includes,variable) 36AC_DEFUN([gt_CHECK_VAR_DECL], 37[ 38 define([gt_cv_var], [gt_cv_var_]$2[_declaration]) 39 AC_MSG_CHECKING([if $2 is properly declared]) 40 AC_CACHE_VAL(gt_cv_var, [ 41 AC_TRY_COMPILE([$1 42 extern struct { int foo; } $2;], 43 [$2.foo = 1;], 44 gt_cv_var=no, 45 gt_cv_var=yes)]) 46 AC_MSG_RESULT($gt_cv_var) 47 if test $gt_cv_var = yes; then 48 AC_DEFINE([HAVE_]translit($2, [a-z], [A-Z])[_DECL], 1, 49 [Define if you have the declaration of $2.]) 50 fi 51]) 52 53# Prerequisites of lib/setenv.c. 54AC_DEFUN([gl_PREREQ_SETENV], 55[ 56 AC_REQUIRE([AC_FUNC_ALLOCA]) 57 AC_CHECK_HEADERS_ONCE(unistd.h) 58 AC_CHECK_HEADERS(search.h) 59 AC_CHECK_FUNCS(tsearch) 60 gt_CHECK_VAR_DECL([#include <unistd.h>], environ) 61]) 62 63# Prerequisites of lib/unsetenv.c. 64AC_DEFUN([gl_PREREQ_UNSETENV], 65[ 66 AC_CHECK_HEADERS_ONCE(unistd.h) 67 gt_CHECK_VAR_DECL([#include <unistd.h>], environ) 68]) 69