1 /* Copyright (C) 2008-2021 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 <https://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 which setting flags according to
25 FLAGS. Return FD2 or -1. */
26 int
__dup3(int fd,int fd2,int flags)27 __dup3 (int fd, int fd2, int flags)
28 {
29 if (fd < 0 || fd2 < 0)
30 {
31 __set_errno (EBADF);
32 return -1;
33 }
34
35 if (fd == fd2)
36 /* No way to check that they are valid. */
37 return fd2;
38
39 __set_errno (ENOSYS);
40 return -1;
41 }
42 libc_hidden_def (__dup3)
43 weak_alias (__dup3, dup3)
44 stub_warning (dup3)
45