1 /* Duplicate an open file descriptor to a specified file descriptor.
3 Copyright (C) 1999, 2004, 2005, 2006, 2007, 2009 Free Software
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 /* written by Paul Eggert */
30 /* On mingw, dup2 exists, but always returns 0 for success. */
32 dup2 (int fd, int desired_fd)
35 int result = dup2 (fd, desired_fd);
41 #else /* !REPLACE_DUP2 */
42 /* On older platforms, dup2 did not exist. */
46 dupfd (int fd, int desired_fd)
48 int duplicated_fd = dup (fd);
49 if (duplicated_fd < 0 || duplicated_fd == desired_fd)
53 int r = dupfd (fd, desired_fd);
55 close (duplicated_fd);
63 dup2 (int fd, int desired_fd)
69 return fcntl (fd, F_DUPFD, desired_fd);
71 return dupfd (fd, desired_fd);
74 #endif /* !REPLACE_DUP2 */