/* Copyright (C) 1998 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, see <http://www.gnu.org/licenses/>. */ #include <errno.h> #include <stdlib.h> #include <sys/ioctl.h> #include <termios.h> /* Unlock the slave pseudo terminal associated with the master pseudo terminal specified by FD. */ int unlockpt (int fd) { #ifdef TIOCSPTLCK int save_errno = errno; int unlock = 0; if (ioctl (fd, TIOCSPTLCK, &unlock)) { if (errno == EINVAL) { errno = save_errno; return 0; } else return -1; } #endif /* If we have no TIOCSPTLCK ioctl, all slave pseudo terminals are unlocked by default. */ return 0; }