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Q
When I drag from my application into a Finder window, the system
crashes. I noticed Finder uses a windowKind value of 20 for its windows,
and so does my app. When my app avoids windowKind 20, everything's
hunky-dory. What gives? A Through the Drag Manager, Finder has gotten access to the windows in your app's window list (specifically, by using undocumented calls to obtain the source window of a drag). If your window's windowKind field is 20, Finder assumes the window is one of its own (as opposed to a driver window, whose windowKind would be negative, or a dialog window, whose windowKind would be 2, etc.). Finder grabs the value in the window's refCon field and type-casts it to a pointer to a C++ object in Finder's heap. I think you can see where this is going: when Finder attempts to dereference the pointer, various crashing behaviors result. The upshot of this Finder bug is that your application should not use windowKind values of 20. [Nov 27 1996] |