The documented error return value for SDL_WaitEvent() is 0.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%40354

src/events/SDL_events.c

@@ -383,7 +383,7 @@ int SDL_WaitEvent (SDL_Event *event)
 	while ( 1 ) {
 		SDL_PumpEvents();
 		switch(SDL_PeepEvents(event, 1, SDL_GETEVENT, SDL_ALLEVENTS)) {
-		    case -1: return -1; 
+		    case -1: return 0;
 		    case 1: return 1;
 		    case 0: SDL_Delay(10);
 		}