title: how to get socket.id of a connection on client side?
body: <p>Im using the following code in index.js</p>
  
  <pre><code>io.on('connection', function(socket){
  console.log('a user connected');
  console.log(socket.id);
  });
  </code></pre>
  
  <p>the above code lets me print the socket.id in console.</p>
  
  <p>But when i try to print the socket.id on client side using the following code</p>
  
  <pre><code>&lt;script&gt;
  var socket = io();
  var id = socket.io.engine.id;
  document.write(id);
  &lt;/script&gt;
  </code></pre>
  
  <p>it gives 'null' as output in the browser.</p>