flat file user

Hi everyone, I have a question, have anyone of you using flat file for user database? If so, Can we use some script to update the content? If so do you guys have some examples? For example if i limited user A to use only 4 hours. and after he use 2 hours, and log out, I want to update the detail file, so user A data will become only 2 hours now. I know we can do that with sql and others . but how about flat file. Need a light here. thanks a lot Priscilla --------------------------------- What are the most popular cars? Find out at Yahoo! Autos