Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!uakari.primate.wisc.edu!ginosko!uunet!yale!eagle!rcook From: rcook@eagle.wesleyan.edu Newsgroups: comp.sys.mac.programmer Subject: A BUG (sort of) in the FINDER Message-ID: <1567@eagle.wesleyan.edu> Date: 24 Sep 89 19:18:53 GMT Lines: 31 Bug in the Finder!! Some time ago I had written a program which ran perfectly, only when it finished and returned to the Finder I discovered that I couldn't double- click on anything anymore; pressing the mouse button twice merely selected the file, but did not open it. This only occurred in the Finder. I could double click to my hearts content in ResEdit or Word or LSP. I suspected that I had clobbered the global variable doubleTime, but I actually hadn't. After some investigation, I discovered that my program sets the system event mask to disable the posting of MouseUp events, and the Finder needs MouseUps to process a double click. I tested this further with this 3 line wonder: program test; begin SetEventMask(EveryEvent - MUpMask); end. And sure enough, no double clicks. All Finders up to the version that goes with System 6.0.3 (and perhaps newer ones) can be brought to their knees by a bad event mask, so watch out. I'm surprised Larry, Steve, John, and Bruce (or whoever they are) didn't set the mask just the way they want it when the Finder starts up. I suppose the rule shoule be that if you mess with the event mask, set it to EveryEvent-KeyUpMask when the program finishes to avoid future problems. Tell me if you know anything more about this stuff. --- Randall Cook rcook%eagle@wesleyan.bitnet rcook@eagle.wesleyan.bitnet