nuttx-apps/examples/ostest/vfork.c

100 lines
3.2 KiB
C

/****************************************************************************
* examples/ostest/vfork.c
*
* Copyright (C) 2013, 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 <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include "ostest.h"
#if defined(CONFIG_ARCH_HAVE_VFORK) && defined(CONFIG_SCHED_WAITPID)
/****************************************************************************
* Private Data
****************************************************************************/
static volatile bool g_vforkchild;
/****************************************************************************
* Public Functions
****************************************************************************/
int vfork_test(void)
{
pid_t pid;
g_vforkchild = false;
pid = vfork();
if (pid == 0)
{
/* There is not very much that the child is permitted to do. Perhaps
* it can just set g_vforkchild.
*/
g_vforkchild = true;
exit(0);
}
else if (pid < 0)
{
printf("vfork_test: vfork() failed: %d\n", errno);
return -1;
}
else
{
sleep(1);
if (g_vforkchild)
{
printf("vfork_test: Child %d ran successfully\n", pid);
}
else
{
printf("vfork_test: ERROR Child %d did not run\n", pid);
return -1;
}
}
return 0;
}
#endif /* CONFIG_ARCH_HAVE_VFORK && CONFIG_SCHED_WAITPID */