Is there any way to ensure that default PHP SESSION garbage collector will call some function on destroying expired session?

From my experience, default PHP garbage collector does not call any callback function on destroying the session.

I guess, the only way would be to define custom session handlers for all 5 operations - open, close, destroy, .. ? (redundant code for me)

The reason is, that I need to adjust counter for active sessions.

Perfect solution would be e.g. if it would be possible to register something like session\_register\_destroy(function) - but I am not sure if this is possible. 

Thank you.