incubator-nuttx/libs/libc/stdlib/lib_unlockpt.c

76 lines
3.0 KiB
C

/****************************************************************************
* libs/libc/stdlib/lib_unlockpt.c
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#ifdef CONFIG_PSEUDOTERM
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: unlockpt
*
* Description:
* The unlockpt() function unlocks the slave pseudoterminal device
* corresponding to the master pseudoterminal referred to by fd.
* unlockpt() must be called before opening the slave side of a
* pseudoterminal.
*
* Returned Value:
* When successful, unlockpt() returns 0. Otherwise, it returns -1 and
* sets errno appropriately.
*
* EBADF - The fd argument is not a file descriptor open for writing.
* EINVAL - The fd argument is not associated with a master
* pseudoterminal
*
****************************************************************************/
int unlockpt(int fd)
{
return ioctl(fd, TIOCSPTLCK, 0);
}
#endif /* CONFIG_PSEUDOTERM */