The Old New Thing

When will GetMessage return -1?

March 22, 2013 Mar 22, 2013 03/22/13

Raymond Chen

A source of great consternation is the mysterious return value from : If there is an error, the return value is −1. For example, the function fails if is an invalid window handle or is an invalid pointer. That paragraph has caused all sorts of havoc, because it throws into disarray the standard message pump: But don't worry, the ...