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/* Copyright (C) 2002-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/file.h>
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
static int fd;
static void *
tf (void *arg)
{
if (flock (fd, LOCK_SH | LOCK_NB) != 0)
{
puts ("second flock failed");
exit (1);
}
pthread_mutex_unlock (&lock);
return NULL;
}
static int
do_test (void)
{
char tmp[] = "/tmp/tst-flock1-XXXXXX";
fd = mkstemp (tmp);
if (fd == -1)
{
puts ("mkstemp failed");
exit (1);
}
unlink (tmp);
write (fd, "foobar xyzzy", 12);
if (flock (fd, LOCK_EX | LOCK_NB) != 0)
{
puts ("first flock failed");
exit (1);
}
pthread_mutex_lock (&lock);
pthread_t th;
if (pthread_create (&th, NULL, tf, NULL) != 0)
{
puts ("pthread_create failed");
exit (1);
}
pthread_mutex_lock (&lock);
void *result;
if (pthread_join (th, &result) != 0)
{
puts ("pthread_join failed");
exit (1);
}
close (fd);
return result != NULL;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
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