How to count messages in the window message queue?

Question

It seems that there's no a documented API to accomplish the subj, but maybe there's an undocumented one, or some trick to do this?

Answer 1

The only two counts you can get are "full" (something like PostMessage fails with the error ERROR_NOT_ENOUGH_QUOTA) and "empty" (PeekMessage returns zero).

If you need any other value, you're probably trying to solve the wrong problem.