title: How can I check if a scrollbar is visible?
body: <p>Is it possible to check the <code>overflow:auto</code> of a div?</p>
  
  <p><em>For example:</em></p>
  
  <p><strong>HTML</strong></p>
  
  <pre><code>&lt;div id="my_div" style="width: 100px; height:100px; overflow:auto;" class="my_class"&gt; 
    * content
  &lt;/div&gt;
  </code></pre>
  
  <p><strong>JQUERY</strong></p>
  
  <pre><code>$('.my_class').live('hover', function (event)
  {
      if (event.type == 'mouseenter')
      {
           if( ...  if scrollbar visible ? ... )
           {
              alert('true'):
           }
           else
           {
              alert('false'):
           }
      }
  
  });
  </code></pre>
  
  <p>Sometimes is the content short (no scrollbar) and sometimes long (scrollbar visible).</p>