how do I declare a variable that any client can access using socket.io

Question

how do I declare a variable that any client can access using socket.io

This is for a gaming application I use MySQL for most of my dirty work but I was hoping for a lightweight solution here.

I've noticed I can declare socket.clientid and every time that client emits to my server I can use socket.clientid

Is there a way to declare a variable like (never tried this but) "io.sockets.doors=[1,0,1]" representing a closed door#1 open door#2 closed door#3 and allow everyone to access a single array from my server's memory? If so is there documentation?

My server is running socket.io in node.js clients are connected via websockets in a browser

node.js
websocket
socket.io

Answer 1

so I tried this and it worked like a charm... I thought it would be easier to ask here than to try it myself and possibly make a mistake and think it didn't work.

io.sockets.a="A varriable declared like this is accessable to any client connected on the listening port"