Where starting to understand midi_server?

This question is for who have still writing a server.

I have the output of "nm midi_server", I know that is an app that is started when 
BeOS begin and finish when BeOS finish.

My first question is : how to acces to function defined in this app, Messaging, Direct 
Access....

with the output of "nm" how define function and parameter that will be defined in the 
app?

A+
Jerome