busybox/miscutils/setsid.c

/* vi: set sw=4 ts=4: */
/*
 * setsid.c -- execute a command in a new session
 * Rick Sladkey <jrs@world.std.com>
 * In the public domain.
 *
 * 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
 * - added Native Language Support
 *
 * 2001-01-18 John Fremlin <vii@penguinpowered.com>
 * - fork in case we are process group leader
 *
 * 2004-11-12 Paul Fox
 * - busyboxed
 */

#include "busybox.h"
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

int setsid_main(int argc, char *argv[])
{
	if (argc < 2)
		bb_show_usage();

	if (getpgrp() == getpid()) {
		switch (fork()){
		case -1:
			bb_perror_msg_and_die("fork");
		case 0:
			break;
		default:	/* parent */
			exit(0);
		}
		/* child falls through */
	}

	setsid();  /* no error possible */

	execvp(argv[1], argv + 1);

	bb_perror_msg_and_die("%s", argv[1]);
}