pfSense

		for ($idx = 0; $idx < 3; $idx++) {

			$upgrade_script = "{$pfsense_upgrade} -y -l " .

			    "{$logfilename}.txt -p {$sock_file}";

			unlink_if_exists($sock_file);

			$execpid = mwexec_bg("{$upgrade_script} {$params}");

			// Make sure the upgrade process starts

			while (posix_kill($execpid, 0) && !file_exists(

			    $sock_file)) {

				sleep(1);

			}

			if (posix_kill($execpid, 0) && file_exists(

			    $sock_file)) {

				$start_polling = true;

				@file_put_contents($gui_pidfile, $execpid);

				@file_put_contents($gui_mode, $mode);

				break;

			}