1/* Invoke dup, but avoid some glitches. 2 Copyright (C) 2001, 2004, 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 Paul Eggert. */ 19 20#ifdef HAVE_CONFIG_H 21# include <config.h> 22#endif 23 24#include "unistd-safer.h" 25 26#include <fcntl.h> 27 28#include <unistd.h> 29#ifndef STDERR_FILENO 30# define STDERR_FILENO 2 31#endif 32 33/* Like dup, but do not return STDIN_FILENO, STDOUT_FILENO, or 34 STDERR_FILENO. */ 35 36int 37dup_safer (int fd) 38{ 39#ifdef F_DUPFD 40 return fcntl (fd, F_DUPFD, STDERR_FILENO + 1); 41#else 42 /* fd_safer calls us back, but eventually the recursion unwinds and 43 does the right thing. */ 44 return fd_safer (dup (fd)); 45#endif 46} 47