1 /* Copyright (C) 1991-2022 Free Software Foundation, Inc.
2 
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <unistd.h>
20 
21 /* Duplicate FD to FD2, closing the old FD2 and making FD2 be
22    open on the same file as FD is.  Return FD2 or -1.  */
23 int
__dup2(int fd,int fd2)24 __dup2 (int fd, int fd2)
25 {
26   int flags = 0;
27 
28   if (fd2 == fd)
29     /* See the comment in dup3.  */
30     flags = -1;
31 
32   return __dup3 (fd, fd2, flags);
33 }
34 libc_hidden_def (__dup2)
35 weak_alias (__dup2, dup2)
36