public function logout()
	{
		$this->debug->groupCollapsed(__METHOD__);
		if ($this->auth) {
			$this->setPersistToken(false);	// more efficient to remove first (while session still exists)
			$this->log('logout');
		}
		ArrayUtil::path($_SESSION, $this->cfg['sessionPath'], array());	// clear session
		$this->userid = null;
		$this->auth = 0;
		$this->debug->groupEnd();
		return;
	}