1 /* Determine the session ID of the controlling terminal of the current process.
2 Copyright (C) 2010-2024 Free Software Foundation, Inc.
4 This file is free software: you can redistribute it and/or modify
5 it under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation, either version 3 of the
7 License, or (at your option) any later version.
9 This file 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
12 GNU Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
19 #define USE_OLD_TTY /* needed on OpenBSD 4.5, so that TIOCGSID gets defined */
25 #include <sys/ioctl.h>
30 #ifdef TIOCGSID /* Mac OS X, OpenBSD */
33 if (ioctl (fd
, TIOCGSID
, &sid
) < 0)
34 return -1; /* errno is set here */
37 #else /* FreeBSD, Cygwin, mingw */