Example_auth 站长写的整合ucenter，求此cookie的来历以及出处？ [ 求助交流 ]

Example_auth 站长写的整合ucenter，求此cookie的来历以及出处？ 这下面的代码是站长写的：

public function init()
{
    Yii::import('application.vendors.*');
    require_once('ucenter.php');
    $model=new LoginForm;
    $cookie = Yii::app()->request->getCookies();

    if(!empty($cookie['Example_auth']->value) && Yii::app()->user->isGuest)
    {
        list($Example_uid, $Example_username) = explode("\t", uc_authcode($cookie['Example_auth']->value, 'DECODE'));
        if(Yii::app()->user->id != $Example_uid)
        {
            $identity=new UserIdentity($Example_username);
            $identity->authenticate();
            Yii::app()->user->login($identity,$cookie['cookietime']->value);
            $this->redirect(Yii::app()->user->returnUrl);
        }
    }

    if(empty($cookie['Example_auth']->value) && !Yii::app()->user->isGuest)
    {
        Yii::app()->user->logout();
        $this->redirect(Yii::app()->homeUrl);
    }
}