Clear cache for user

Hi

I’m caching content for logged in users.

Is there a function to clear the cache for a specific URL and logged in user?

Ie I need a function like this:

wp_sc_clear_url_for_user($url, $user_id);

If not how does super cache determine the filenane of the files it creates for each user? As if I knew that I could write my own function.

Pete