Function to list all windows opened by the current process?

["Peter Hildebrandt" <peter hildebrandt gmail com>]

Hi *,

is there a function I can use to get a list of all windows opened by the  
process currently running?  The idea is to cleanly terminate all windows  
once the application window has been closed and gtk_main returned.

I have looked around the API docs but did not find a good way to do this.   
So I am about to write my own book keeping, but I'd like to make sure that  
I am not duplicating some functionality already present in GTK.

Thanks for your help,

Peter