<html>
  <head>
    <script>
      function onload() {
        try {
          document.title = document.getElementById("frame").contentWindow.location.href;
        } catch (e) {
          document.title = "Exception";
        }
      }
    </script>
  </head>
  <body onload="onload()">
    <iframe id="frame" src="hello_world.html"></iframe>
  </body>
</html>