Socket

All the Socket behavior is defined here.

The app/config/socket.js is a function that receives the io object (an instance of Socket.io) and the sessionSockets (only if you has sessions enabled, it's an instance of session.socket.io) as arguments, so you can create the rooms, messagens, listeners and so on.

All the socket advanced options must also be done here using the method io.set(property, value).