Merge commit 'snapstart' into stable

[gnulib.git] / m4 / popen.m4

diff --git a/m4/popen.m4 b/m4/popen.m4
index 76fd6d9..7477923 100644 (file)
--- a/m4/popen.m4
+++ b/m4/popen.m4
@@ -1,5 +1,5 @@
-# popen.m4 serial 2
-dnl Copyright (C) 2009, 2010 Free Software Foundation, Inc.
+# popen.m4 serial 3
+dnl Copyright (C) 2009-2011 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.
@@ -11,11 +11,16 @@ AC_DEFUN([gl_FUNC_POPEN],
     [gl_cv_func_popen_works],
     [
       AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
-]], [FILE *child;
+]], [int result = 0;
+     FILE *child;
      fclose (stdin);
      fclose (stdout);
      child = popen ("echo a", "r");
-     return !(fgetc (child) == 'a' && pclose (child) == 0);
+     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'])