1 /* Invoke pipe, but avoid some glitches. 2 Copyright (C) 2005-2006, 2009-2012 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 3 of the License, or 7 (at your option) 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, see <http://www.gnu.org/licenses/>. */ 16 17 /* Written by Jim Meyering. */ 18 19 #include <config.h> 20 21 #include "unistd-safer.h" 22 23 #include <unistd.h> 24 #include <errno.h> 25 26 /* Like pipe, but ensure that neither of the file descriptors is 27 STDIN_FILENO, STDOUT_FILENO, or STDERR_FILENO. Fail with ENOSYS on 28 platforms that lack pipe. */ 29 30 int 31 pipe_safer (int fd[2]) 32 { 33 #if HAVE_PIPE 34 if (pipe (fd) == 0) 35 { 36 int i; 37 for (i = 0; i < 2; i++) 38 { 39 fd[i] = fd_safer (fd[i]); 40 if (fd[i] < 0) 41 { 42 int e = errno; 43 close (fd[1 - i]); 44 errno = e; 45 return -1; 46 } 47 } 48 49 return 0; 50 } 51 #else 52 errno = ENOSYS; 53 #endif 54 55 return -1; 56 } 57
