Directory Authentication for log-in solution

[Mark Nolan]

Any leads or ideas for using mySQL to support a single log-in screen at a root domain but restrict access to certain directories on a server? Ideally, the user will log-in, based on their username and password, and then be directed to a particular directory to use a script. If the log-in can assign access to only a particular directory, how can we then pass the value to other programs running in the assigned directory to illinimate the ned to log-in twice?

Any advice or sources would be helpful.

Mark