coreutils/lib/dup-safer.c
2005-05-14 07:58:06 +00:00

51 lines
1.4 KiB
C

/* Invoke dup, but avoid some glitches.
Copyright (C) 2001, 2004, 2005 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
/* Written by Paul Eggert. */
#if HAVE_CONFIG_H
# include <config.h>
#endif
#include "unistd-safer.h"
#if HAVE_FCNTL_H
# include <fcntl.h>
#endif
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifndef STDERR_FILENO
# define STDERR_FILENO 2
#endif
/* Like dup, but do not return STDIN_FILENO, STDOUT_FILENO, or
STDERR_FILENO. */
int
dup_safer (int fd)
{
#ifdef F_DUPFD
return fcntl (fd, F_DUPFD, STDERR_FILENO + 1);
#else
/* fd_safer calls us back, but eventually the recursion unwinds and
does the right thing. */
return fd_safer (dup (fd));
#endif
}