1.js

<script src="https://cdn.pubnub.com/sdk/javascript/pubnub.4.17.0.js"></script>
<script src="http://d3js.org/d3.v3.min.js" charset="utf-8"></script>
<script src="../js/c3.js"></script>
<script src="../js/pubnub-c3.js"></script>

2.js

<div id="chart"></div>
<script>
var chart = pubnubC3({
  channel: "c3-spline",
  generate: {
    bindto: '#chart',
    data: {
      x: 'x',
      columns: [],
      labels: true
    },
    axis : {
      x : {
        type : 'timeseries',
        tick: {
          format: '%H:%M:%S'
        }
      }
    }
  }
});
</script>

3.js

var pubnub = new PubNub({
    subscribeKey: "demo",
    publishKey: "demo",
    ssl: true
})

setInterval(function(){

  pubnub.publish({
    channel: 'c3-spline',
    message: {
      columns: [
        ['x', new Date().getTime()],
        ['Austin', Math.floor(Math.random() * 99)],
        ['New York', Math.floor(Math.random() * 99)],
        ['San Francisco', Math.floor(Math.random() * 99)],
        ['Portland', Math.floor(Math.random() * 99)]

      ]
    }
  });
}, 1000);