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/*
* Copyright (c) 2000 Kungliga Tekniska H�gskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* 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 of the Institute 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 INSTITUTE 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 INSTITUTE 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.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/stat.h>
#include <err.h>
#include <roken.h>
RCSID("$KTH: pine.c,v 1.3 2000/10/03 00:35:13 lha Exp $");
#define LOCK "mailbox-name.lock"
int
main(int argc, char *argv[])
{
int ret;
struct stat sb;
char unique[1024];
int retrycount = 0;
set_progname (argv[0]);
snprintf (unique, sizeof(unique), LOCK ".%d.%d",
getpid(), (int)time(NULL));
ret = umask(077);
if (ret < 0)
err (1, "umask");
ret = open(unique, O_WRONLY|O_CREAT|O_EXCL, 0666);
if (ret < 0)
errx (1, "open");
close (ret);
retry:
retrycount++;
if (retrycount > 10000000)
errx (1, "failed getting the lock");
ret = link(unique, LOCK);
if (ret < 0)
goto retry;
ret = stat(unique, &sb);
if (ret < 0)
errx (1, "stat");
if (sb.st_nlink != 2)
goto retry;
ret = chmod (LOCK, 0666);
if (ret < 0)
errx (1, "chmod");
ret = unlink (LOCK);
if (ret < 0)
err (1, "unlink " LOCK);
ret = unlink (unique);
if (ret < 0)
err (1, "unlink: %s", unique);
return 0;
}
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