empserver/src/lib/gen/disassoc.c

81 lines
2.1 KiB
C

/*
* Empire - A multi-player, client/server Internet based war game.
* Copyright (C) 1986-2013, Dave Pare, Jeff Bailey, Thomas Ruschak,
* Ken Stevens, Steve McClure, Markus Armbruster
*
* Empire 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/>.
*
* ---
*
* See files README, COPYING and CREDITS in the root of the source
* tree for related information and legal notices. It is expected
* that future projects/authors will amend these files as needed.
*
* ---
*
* disassoc.c: Boilerplate daemonization code
*
* Known contributors to this file:
* Doug Hay, 1998
* Markus Armbruster, 2005
*/
/*
* See W. Richard Stevens: UNIX Network Programming, Vol. 1
*/
#include <config.h>
#ifndef _WIN32
#include <fcntl.h>
#include <sys/types.h>
#include <unistd.h>
#include "prototypes.h"
int
disassoc(void)
{
pid_t pid;
int i;
if ((pid = fork()) < 0)
return -1;
else if (pid)
_exit(0); /* parent */
/* Become session leader of new session, lose controlling tty */
if (setsid() < 0)
return -1;
/* Lose session leader status, so we can't acquire a controlling tty */
if ((pid = fork()) < 0)
return -1;
else if (pid)
_exit(0); /* parent */
/* Note: no controlling tty, therefore no SIGHUP sent */
/* datadir is working directory, that's fine */
/* We opened a bunch of files already, so just close 0..2 */
for (i = 0; i < 3; i++)
close(i);
/* Library code may use 0..2; make sure that's safe */
open("/dev/null", O_RDWR);
dup(0);
dup(0);
return 0;
}
#endif