how to call socket.io.emit from other call back function in other port in node.js

what I want to do is from the client to run a function in node.js, this call back function call to socket.io.emit, to make notifications to another client, is this possible? The callback function is listening for a port other than the socket, if they have some serious example of great help, simulating push notifications, it should be clear that I am really new to node.js thanks regards

via Diego Rivon