blob: fa3c5d59a54f93bbe9d7dfe71ccb680fad11ef4f [file] [log] [blame]
lh9ed821d2023-04-07 01:36:19 -07001/* Copyright (C) 1991-2015 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library 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 GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <fcntl.h>
20#include <unistd.h>
21
22
23/* Duplicate FD to FD2, closing the old FD2 and making FD2 be
24 open the same file as FD is. Return FD2 or -1. */
25int
26__dup2 (fd, fd2)
27 int fd;
28 int fd2;
29{
30 if (fd < 0 || fd2 < 0)
31 {
32 __set_errno (EBADF);
33 return -1;
34 }
35
36 if (fd == fd2)
37 /* No way to check that they are valid. */
38 return fd2;
39
40 __set_errno (ENOSYS);
41 return -1;
42}
43libc_hidden_def (__dup2)
44stub_warning (dup2)
45
46weak_alias (__dup2, dup2)