Question

I’m trying to call an objective-C function from a C function but the code keeps crashing in objc_msgSend.

My objective-C class is a singleton and I’m using the following code.

void c_function(int arg0, const char *arg1)  
{  
   [[objc_class instance] testFunction:arg0 Arg1:arg1];  
}

The gdb shows the crash is happening when objective-C function is being invoked. How cal I call an objective-C function from within a c function?

Thanks

Answer 1

There’s nothing wrong with your code as there are no special rules for calling objc methods from c functions. If there is a crash in objc_msgSend, then refer to http://www.sealiesoftware.com/blog/archive/2008/09/22/objc_explain_So_you_crashed_in_objc_msgSend.html. The same thing would have happened if the objc line was in other objc code — it’s likely you forgot to retain the shared instance of your singleton.