Does CallWindowProc do anything besides calling lpPrevWndFunc with needed parameters? e.g. can it be used to call ANY code with stdcall and 4 parameters?
It looks like it does a fair amount of processing... haven't looked into it, though.
Supposedly, you have to pass whatever is found in GWL_WNDPROC, because in future versions it might not be a pointer but some kind of handle (I recall reading that somewhere in win32.hlp). Besides it must be doing further processing, or calling the function directly would work just the same... :?