1 /* Copyright (C) 1998-2022 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 <paths.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <unistd.h>
22 #include <errno.h>
23
24
25 /* Unlock the slave pseudo terminal associated with the master pseudo
26 terminal specified by FD. */
27 int
unlockpt(int fd)28 unlockpt (int fd)
29 {
30 char buf[sizeof (_PATH_TTY) + 2];
31
32 /* BSD doesn't have a lock, but it does have `revoke'. */
33 if (__ptsname_r (fd, buf, sizeof (buf)))
34 {
35 if (errno == ENOTTY)
36 __set_errno (EINVAL);
37 return -1;
38 }
39 return __revoke (buf);
40 }
41 libc_hidden_def (unlockpt)
42