stdio-common/tst-fileno.c

   1 /* Copyright (C) 1994, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <stdio.h>
  20 #include <unistd.h>
  21
  22 static int
  23 check (const char *name, FILE *stream, int fd)
  24 {
  25   int sfd = fileno (stream);
  26   printf ("(fileno (%s) = %d) %c= %d\n", name, sfd, sfd == fd ? '=' : '!', fd);
  27   return sfd != fd;
  28 }
  29
  30 int
  31 main (void)
  32 {
  33   exit (check ("stdin", stdin, STDIN_FILENO) ||
  34         check ("stdout", stdout, STDOUT_FILENO) ||
  35         check ("stderr", stderr, STDERR_FILENO));
  36 }