Trying to implement MIDIReceived but I don't know where the results are sent

I would like to implement MIDIReceived in a Objective C Program:

extern OSStatus MIDIReceived(MIDIEndpointRef src,const MIDIPacketList *pktlist);

Where would I put the code to utilize the src and pktlist variables once they are sent?

I've been trying to read about the extern OSStatus part of the code but I havn't been able to find anything. Any bumps in the right direction would开发者_JAVA技巧 be greatly appreciated.

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The extern declaration just hints to the compiler that there exists somewhere a function with that definition. You can put that code anywhere else, but it at least has to be somewhere or else you'll get a linker error during building.

For more information, I suggest reading up on the following:

• http://en.wikipedia.org/wiki/External_variable#Definition.2C_declaration_and_the_extern_keyword
• http://www.geeksforgeeks.org/archives/840

As for OSStatus, that's just a return code on OSX.