-#serial 1
+# fflush.m4 serial 6
-# Copyright (C) 2007 Free Software Foundation, Inc.
+# Copyright (C) 2007-2008 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
#include <stdio.h>
#include <unistd.h>
]], [[FILE *f = fopen ("conftest.txt", "r");
- char buffer[10];
- int fd = fileno (f);
- if (!f || 0 > fd || fread (buffer, 1, 5, f) != 5)
+ char buffer[10];
+ int fd;
+ if (f == NULL)
+ return 1;
+ fd = fileno (f);
+ if (fd < 0 || fread (buffer, 1, 5, f) != 5)
return 2;
/* For deterministic results, ensure f read a bigger buffer. */
if (lseek (fd, 0, SEEK_CUR) == 5)
/* POSIX requires fflush-fseek to set file offset of fd. */
if (fflush (f) != 0 || fseek (f, 0, SEEK_CUR) != 0)
return 4;
- return !(lseek (fd, 0, SEEK_CUR) == 5);
+ if (lseek (fd, 0, SEEK_CUR) != 5)
+ return 5;
+ /* TODO: Verify behaviour of fflush after ungetc, see
+ <http://lists.gnu.org/archive/html/bug-gnulib/2008-03/msg00131.html>. */
+ return 0;
]])], [gl_cv_func_fflush_stdin=yes], [gl_cv_func_fflush_stdin=no],
[dnl Pessimistically assume fflush is broken. This is wrong for
dnl at least glibc and cygwin; but lib/fflush.c takes this into account.
AC_DEFUN([gl_REPLACE_FFLUSH],
[
AC_LIBOBJ([fflush])
+ AC_LIBOBJ([fseeko])
AC_REQUIRE([gl_STDIO_H_DEFAULTS])
REPLACE_FFLUSH=1
+ REPLACE_FSEEKO=1
+ gl_PREREQ_FFLUSH
+])
+
+# Prerequisites of lib/fflush.c.
+AC_DEFUN([gl_PREREQ_FFLUSH],
+[
+ AC_REQUIRE([AC_C_INLINE])
+ :
])