1/* Invoke dup, but avoid some glitches. 2 3 Copyright (C) 2001, 2004, 2005, 2006 Free Software Foundation, Inc. 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 2, or (at your option) 8 any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; if not, write to the Free Software Foundation, 17 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ 18 19/* Written by Paul Eggert. */ 20 21#include <config.h> 22 23#include "unistd-safer.h" 24 25#include <fcntl.h> 26 27#include <unistd.h> 28#ifndef STDERR_FILENO 29# define STDERR_FILENO 2 30#endif 31 32/* Like dup, but do not return STDIN_FILENO, STDOUT_FILENO, or 33 STDERR_FILENO. */ 34 35int 36dup_safer (int fd) 37{ 38#if defined F_DUPFD && !defined FCHDIR_REPLACEMENT 39 return fcntl (fd, F_DUPFD, STDERR_FILENO + 1); 40#else 41 /* fd_safer calls us back, but eventually the recursion unwinds and 42 does the right thing. */ 43 return fd_safer (dup (fd)); 44#endif 45} 46