external/gpl2/xcvs/dist/lib/pipe-safer.c

   1 /* Invoke pipe, but avoid some glitches.
   2    Copyright (C) 2005 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  17
  18 /* Written by Jim Meyering.  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 # include <config.h>
  22 #endif
  23
  24 #include "unistd-safer.h"
  25
  26 #include <unistd.h>
  27
  28 /* Like pipe, but ensure that neither of the file descriptors is
  29    STDIN_FILENO, STDOUT_FILENO, or STDERR_FILENO.  */
  30
  31 int
  32 pipe_safer (int fd[2])
  33 {
  34   int fail = pipe (fd);
  35   if (fail)
  36     return fail;
  37
  38   {
  39     int i;
  40     for (i = 0; i < 2; i++)
  41       {
  42         int f = fd_safer (fd[i]);
  43         if (f < 0)
  44           return -1;
  45         fd[i] = f;
  46       }
  47   }
  48
  49   return 0;
  50 }