Can a WindowProc be called from within itself with a CallWindowProc? (recursively)
That would not be advisable IMHO, anything that is done in the WindowProc can be accomplished using PostMessage as the WindowProc only handles messages anyway. This will allow time critical messages to be processed. There could also be a danger of a stack overflow and you would have to be very careful to eliminate all possiblity of an infinite loop. For my coding purposes I have never found a reason for it but a proc is a proc, it can be called recursively.