incubator-nuttx/libc/termios/lib_tcflow.c

86 lines
3.6 KiB
C

/****************************************************************************
* libc/termios/lib_tcflow.c
*
* Copyright (C) 2017 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 <termios.h>
#include <errno.h>
#include <nuttx/serial/tioctl.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tcflow
*
* Descripton:
* The tcflow() function will suspend or restart transmission or reception
* of data on the object referred to by 'fd', depending on the value of
* 'action'.
*
* Input Parameters:
* fd - An open file descriptor associated with a terminal.
* action - Describes the action to be performed:
* TCOOFF - Output will be suspended.
* TCOON - Suspended output will be restarted.
* TCIOFF - The system will transmit a STOP character, which is
* intended to cause the terminal device to stop
* transmitting data to the system.
* TCION - The system will transmit a START character, which is
* intended to cause the terminal device to start
* transmitting data to the system.
*
* The default on the opening of a terminal file is that neither its input nor
* its output are suspended.
*
* Returned Value:
* Upon successful completion, 0 is returned. Otherwise, -1 is returned and
* errno is set to indicate the nature of the error.
*
****************************************************************************/
int tcflow(int fd, int action)
{
return ioctl(fd, TCXONC, (unsigned long)action);
}