How To Set Session File Name ?

How can I create session files with a specific name ? For example :

my user id : 154423

I want my session file name be : 154423

Any suggestion ? Also is there a way to read the timestamp on a session

file using Yii libraries ?

You have to set useCustomStorage property of CHttpSession to true and implement openSession, writeSession, closeSession, etc. in your own Session class which should extend from CHttpSession.