Function daemonize

daemonize.c:207–371

! * \brief daemon init * \param name daemon name * \param own_pgid daemon process group * \return return 0 on success, -1 on error */

 * \return return 0 on success, -1 on error
 */
int daemonize(char* name, int * own_pgid)
{
	FILE *pid_stream = NULL;
	pid_t pid;
	int r, p,rc;
	int pid_items;

	p=-1;

	if ( (startup_wdir=getcwd(NULL,0))==NULL) {
		LM_ERR("failed to determin the working dir %d/%s\n", errno,
			strerror(errno));
		goto error;
	}

	/* flush std file descriptors to avoid flushes after fork
	 *  (same message appearing multiple times)
	 *  and switch to unbuffered
	 */
	setbuf(stdout, 0);
	setbuf(stderr, 0);
	if (chroot_dir&&(chroot(chroot_dir)<0)){
		LM_CRIT("Cannot chroot to %s: %s\n", chroot_dir, strerror(errno));
		goto error;
	}

	if (chdir(working_dir)<0){
		LM_CRIT("Cannot chdir to %s: %s\n", working_dir, strerror(errno));
		goto error;
	}

	if (!no_daemon_mode) {
		/* fork to become!= group leader*/
		if ((pid=fork())<0){
			LM_CRIT("Cannot fork:%s\n", strerror(errno));
			goto error;
		}else if (pid!=0){
			/* parent process => wait for status codes from children*/
			clean_write_pipeend();
			LM_DBG("waiting for status code from children\n");
			rc = wait_for_all_children();
			LM_INFO("pre-daemon process exiting with %d\n",rc);
			exit(rc);
		}

		/* cleanup read end - nobody should
		 * need to read from status pipe from this point on */
		clean_read_pipeend();

		/* become session leader to drop the ctrl. terminal */
		if (setsid()<0){
			LM_WARN("setsid failed: %s\n",strerror(errno));
		}else{
			*own_pgid=1;/* we have our own process group */
		}
		/* fork again to drop group  leadership */
		if ((pid=fork())<0){
			LM_CRIT("Cannot fork: %s\n", strerror(errno));