public function setMaintenanceMode($value) {
		if ($value === false) {
			if (!file_exists($this->file)) {
				return true;
			}
			return unlink($this->file);
		}

		if ($value) {
			$value = time() + $value * MINUTE;
		}

		return (bool)file_put_contents($this->file, $value);
	}