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/* This testcase is part of GDB, the GNU debugger.
Copyright 2015 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <assert.h>
#include <pthread.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
/* Number of times the main process forks. */
#define NFORKS 10
/* Number of threads by each fork child. */
#define NTHREADS 10
static void *
thread_func (void *arg)
{
/* Empty. */
}
static void
fork_child (void)
{
pthread_t threads[NTHREADS];
int i;
int ret;
for (i = 0; i < NTHREADS; i++)
{
ret = pthread_create (&threads[i], NULL, thread_func, NULL);
assert (ret == 0);
}
for (i = 0; i < NTHREADS; i++)
{
ret = pthread_join (threads[i], NULL);
assert (ret == 0);
}
}
int
main (void)
{
pid_t childs[NFORKS];
int i;
int status;
int num_exited = 0;
/* Don't run forever if the wait loop below gets stuck. */
alarm (180);
for (i = 0; i < NFORKS; i++)
{
pid_t pid;
pid = fork ();
if (pid > 0)
{
/* Parent. */
childs[i] = pid;
}
else if (pid == 0)
{
/* Child. */
fork_child ();
return 0;
}
else
{
perror ("fork");
return 1;
}
}
while (num_exited != NFORKS)
{
pid_t pid = wait (&status);
if (pid == -1)
{
perror ("wait");
return 1;
}
if (WIFEXITED (status))
{
num_exited++;
}
else
{
printf ("Hmm, unexpected wait status 0x%x from child %d\n", status,
pid);
}
}
return 0;
}
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