1 | /* Copyright (C) 1998-2019 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998. |
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 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <errno.h> |
20 | #include <stdlib.h> |
21 | #include <sys/ioctl.h> |
22 | #include <termios.h> |
23 | |
24 | |
25 | /* Unlock the slave pseudo terminal associated with the master pseudo |
26 | terminal specified by FD. */ |
27 | int |
28 | unlockpt (int fd) |
29 | { |
30 | #ifdef TIOCSPTLCK |
31 | int save_errno = errno; |
32 | int unlock = 0; |
33 | |
34 | if (__ioctl (fd, TIOCSPTLCK, &unlock)) |
35 | { |
36 | if (errno == EINVAL) |
37 | { |
38 | __set_errno (save_errno); |
39 | return 0; |
40 | } |
41 | else |
42 | return -1; |
43 | } |
44 | #endif |
45 | /* If we have no TIOCSPTLCK ioctl, all slave pseudo terminals are |
46 | unlocked by default. */ |
47 | return 0; |
48 | } |
49 | |