1 /* closexec.c - set or clear the close-on-exec descriptor flag
2 Copyright (C) 1991, 2004, 2005 Free Software Foundation, Inc.
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.
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.
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.
18 The code is taken from glibc/manual/llio.texi */
20 #ifdef HAVE_CONFIG_H
21 # include <config.h>
22 #endif
24 #include "cloexec.h"
26 #include <unistd.h>
27 #include <fcntl.h>
29 #ifndef FD_CLOEXEC
30 # define FD_CLOEXEC 1
31 #endif
33 /* Set the `FD_CLOEXEC' flag of DESC if VALUE is true,
34 or clear the flag if VALUE is false.
35 Return 0 on success, or -1 on error with `errno' set. */
37 int
38 set_cloexec_flag (int desc, bool value)
39 {
40 #if defined F_GETFD && defined F_SETFD
42 int flags = fcntl (desc, F_GETFD, 0);
44 if (0 <= flags)
45 {
46 int newflags = (value ? flags | FD_CLOEXEC : flags & ~FD_CLOEXEC);
48 if (flags == newflags
49 || fcntl (desc, F_SETFD, newflags) != -1)
50 return 0;
51 }
53 return -1;
55 #else
57 return 0;
59 #endif
60 }