socket.io private message

I've beeen scouring the Net with no luck. I'm trying to figure out how to send a private message from one user to another. There are lots of snippets, but I'm not sure about the client/server interaction. If I have the ID of the socket I want to send to, how do I send it to the server, and how do I ensure the server only sends the message to that one receiver socket?

Is there a tutorial or walkthrough that anyone knows of?

Here's a code snippet that should help

Client side (sending message)

   socket.emit("private", { msg: chatMsg.val(), to: selected.text() });

where 'to' refers to the id to send private message to and 'msg' is the content

Client side (receiving message)

   socket.on("private", function(data) {    
   chatLog.append('<li class="private"><em><strong>'+ data.from +' -> '+ data.to +'</strong>: '+ data.msg +'</em></li>');

where chatLog is a div displaying the chat messages

Server side

   client.on("private", function(data) {        
        io.sockets.sockets[data.to].emit("private", { from: client.id, to: data.to, msg: data.msg });
   client.emit("private", { from: client.id, to: data.to, msg: data.msg });
   });

No tutorial needed. The Socket.IO FAQ is pretty straightforward on this one:

socket.emit('news', { hello: 'world' });

EDIT: Folks are linking to this question when asking about how to get that socket object later. There is no need to. When a new client connects, save a reference to that socket on whatever object you're keeping your user information on. My comment from below:

In the top of your script somewhere, setup an object to hold your users' information.

var connectedUsers = {};

In your .on('connection') function, add that socket to your new object. connectedUsers[USER_NAME_HERE] = socket; Then you can easily retrieve it later. connectedUsers[USER_NAME_HERE].emit('something', 'something');

The easiest way I can think of is to have an hash of all the users on using their id or name as the key and have their socket as part of the value then when you want to send a message to just them you pull that socket and emit on it... something like this:

users[toUser].emit('msg',"Hello, "+toUser+"!");