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I have been getting some Signal 5 SIGTRAP errors… and have been over and over the code and simply can’t see what is creating them.

Can anybody give me ore info on what exactly a Signal 5 SIGTRAP error entails.. what should I be looking for to fix it? All I know is tat it’s some kind of ‘break-point’ error, but I have no breakpoints set in my code (i don’t think!?!)

Thanks for your input (I’m pulling my hair out)…

SIGTRAP is a Unix “signal”. In my experience, if you’re getting unexpected General/SIGTRAPs, it means you’ve tried to access a pointer that’s already been freed.

In Cocoa terms, this means you’ve tried to send a message to an object that’s been dealloc’ed. This usually occurs if you don’t match up calls to the object’s retain method with calls to its release method properly.


SIGTRAP is used by debuggers so that you can control the execution of your program if you don’t have (or can’t use) hardware breakpoints.

What do you mean by SIGTRAP errors?, though? Is your programming terminating with signal 5, or something? I didn’t think that an unhandled signal 5 resulted in termination.

OP - Yeah the app was terminating with a Signal 5. I have tracked down the problem, and it was to do with retaining/releasing problems with my objects. Strange because I was expecting Signal 10 or 11 for those kind of errors.

See also: General/SignalsSentOnCrash