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- /****************************************************************************
- * sched/signal/sig_pause.c
- *
- * Copyright (C) 2012, 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 <unistd.h>
- #include <signal.h>
- #include <errno.h>
- #include <nuttx/signal.h>
- #include <nuttx/cancelpt.h>
- /****************************************************************************
- * Public Functions
- ****************************************************************************/
- /****************************************************************************
- * Name: pause
- *
- * Description:
- * The pause() function will suspend the calling thread until delivery of a
- * non-blocked signal.
- *
- * Input Parameters:
- * None
- *
- * Returned Value:
- * Since pause() suspends thread execution indefinitely unless interrupted
- * a signal, there is no successful completion return value. A value of -1
- * will always be returned and errno set to indicate the error (EINTR).
- *
- * POSIX compatibility:
- * In the POSIX description of this function is the pause() function will
- * suspend the calling thread until delivery of a signal whose action is
- * either to execute a signal-catching function or to terminate the
- * process. This implementation only waits for any non-blocked signal
- * to be received.
- *
- ****************************************************************************/
- int pause(void)
- {
- sigset_t set;
- int ret;
- /* pause() is a cancellation point */
- (void)enter_cancellation_point();
- /* Set up for the sleep. Using the empty set means that we are not
- * waiting for any particular signal. However, any unmasked signal
- * can still awaken sigtimedwait().
- */
- (void)sigemptyset(&set);
- /* sigtwaitinfo() cannot succeed. It should always return error EINTR
- * meaning that some unblocked signal was caught.
- */
- ret = nxsig_waitinfo(&set, NULL);
- if (ret < 0)
- {
- set_errno(-ret);
- ret = ERROR;
- }
- leave_cancellation_point();
- return ret;
- }
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