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/* Tests for fork in multi-threaded environment.
Copyright (C) 2000 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 2000.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <error.h>
#include <stdlib.h>
#include <pthread.h>
#include <unistd.h>
#include <wait.h>
enum
{
PREPARE_BIT = 1,
PARENT_BIT = 2,
CHILD_BIT = 4
};
static int var;
static void
prepare (void)
{
var |= PREPARE_BIT;
}
static void
parent (void)
{
var |= PARENT_BIT;
}
static void
child (void)
{
var |= CHILD_BIT;
}
static void *thread (void *arg);
int
main (void)
{
pthread_t th;
void *res;
pthread_atfork (prepare, parent, child);
if (pthread_create (&th, NULL, thread, NULL) != 0)
error (EXIT_FAILURE, 0, "cannot create thread");
pthread_join (th, &res);
return (int) res;
}
static void *
thread (void *arg)
{
int status;
pid_t pid;
pid = fork ();
if (pid == 0)
{
/* We check whether the `prepare' and `child' function ran. */
exit (var != (PREPARE_BIT | CHILD_BIT));
}
else if (pid == (pid_t) -1)
error (EXIT_FAILURE, errno, "cannot fork");
if (waitpid (pid, &status, 0) != pid)
error (EXIT_FAILURE, errno, "wrong child");
if (WTERMSIG (status) != 0)
error (EXIT_FAILURE, 0, "Child terminated incorrectly");
status = WEXITSTATUS (status);
if (status == 0)
status = var != (PREPARE_BIT | PARENT_BIT);
return (void *) status;
}
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