Return the list of windows matching ONLY and not matching EXCEPT. The windows are returned their stacking order (top first) if BY-STACKING is #t (and that option omits iconified windows). They are returned sorted by their last focussed time (most recently focussed first) if BY-FOCUS is #t. If REVERSE is true, they are returned in the reverse of the usual order. ONLY and EXCEPT each are procedures which take a single window argument and returns #t if the window should be included (for ONLY) or excluded (for EXCEPT), or #f otherwise.