-# popen.m4 serial 1
-dnl Copyright (C) 2009 Free Software Foundation, Inc.
+# popen.m4 serial 5
+dnl Copyright (C) 2009-2014 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([gl_FUNC_POPEN],
[
AC_REQUIRE([gl_STDIO_H_DEFAULTS])
- AC_CACHE_CHECK([whether popen works with closed stdin],
- [gl_cv_func_popen_works],
- [
- AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
-]], [FILE *child;
- fclose (stdin);
- fclose (stdout);
- child = popen ("echo a", "r");
- return !(fgetc (child) == 'a' && pclose (child) == 0);
-])], [gl_cv_func_popen_works=yes], [gl_cv_func_popen_works=no],
- dnl For now, only cygwin 1.5 or older is known to be broken.
- [gl_cv_func_popen_works='guessing yes'])
- ])
- if test "$gl_cv_func_popen_works" = no; then
- REPLACE_POPEN=1
- AC_LIBOBJ([popen])
- gl_PREREQ_POPEN
+ AC_CHECK_FUNCS_ONCE([popen])
+ if test $ac_cv_func_popen = no; then
+ HAVE_POPEN=0
+ else
+ AC_CACHE_CHECK([whether popen works with closed stdin],
+ [gl_cv_func_popen_works],
+ [
+ AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <stdio.h>]],
+ [[int result = 0;
+ FILE *child;
+ fclose (stdin);
+ fclose (stdout);
+ child = popen ("echo a", "r");
+ if (fgetc (child) != 'a')
+ result |= 1;
+ if (pclose (child) != 0)
+ result |= 2;
+ return result;
+ ]])],
+ [gl_cv_func_popen_works=yes],
+ [gl_cv_func_popen_works=no],
+ dnl For now, only cygwin 1.5 or older is known to be broken.
+ [gl_cv_func_popen_works='guessing yes'])
+ ])
+ if test "$gl_cv_func_popen_works" = no; then
+ REPLACE_POPEN=1
+ fi
fi
])
# Prerequisites of lib/popen.c.
AC_DEFUN([gl_PREREQ_POPEN],
[
- AC_REQUIRE([AC_C_INLINE])
+ :
])