Question

I managed to create a bug where a cocoa program is exiting.

-[NSApplication terminate:] is apparently not called.

Nor is -[NSException init].

There is no crash. What I am seeing in gdb is that exit() is being called directly from NSApplicationMain without going through the normal [NSApplication terminate] path.

Any ideas about how to debug this and/or how this (seemingly “impossible” behavior) could happen?

Thanks in advance from a cocoa newb.

Answer 1

After mulling this over I guessed that I was doing something wrong “in the big picture”. So, “in the big picture”, what I was doing is calling a modal dialog (by loading a window nib, showing the window and then using [NSApplication beginModalSessionForWindow]…[NSApp runModalSession]… and upon close [NSApp endModalSession]. This has worked for me in other chunks of code no big deal. The critical difference was that this modal window was being loaded and run out of another class’s awakeFromNib.

I wrote a simple app that will reproduce this behavior. So what happens is that the modal dialog loads happily and when you close the modal window not only does it close but the app exits. I imagine that this is an “as designed” behavior. I was reading up in apple docs to see if I could understand why this was so but I am will muddled on it. I surmise that somehow my dialog’s modal event loop has hijacked the app’s event loop so that when the dialog ends so does the app.

If anybody has a better understanding of this mistake please feel free to enlighten us…

Thanks to all for reading and suggestions.