title: how does cobj work in typo3 extension?
body: <p>I am reading one typo3 extension file:</p>
  
  <p>class.tx_jcjob_pi1.php</p>
  
  <pre><code>...
  $this-&gt;template = $this-&gt;cObj-&gt;fileResource($this-&gt;conf['templateFile']);
  ...
  </code></pre>
  
  <p>class.tslib_pibase.php</p>
  
  <pre><code>...
  var $cObj;
  ...
  </code></pre>
  
  <p>class.tslib_content.php</p>
  
  <pre><code>...
  function fileResource
  ...
  </code></pre>
  
  <p>Question:
  How  does this line work:<code>$this-&gt;cObj-&gt;fileResource($this-&gt;conf['templateFile']);</code>? </p>
  
  <ol>
  <li><p>there is not such codes: such as <code>$cObj = new tslib_cObj()</code>, how did <code>$cObj</code> get instantiated?</p></li>
  <li><p>there is no such codes like <code>require_once('class.tslib_content.php');</code> how could <code>$this-&gt;cObj</code> use the method in <code>class.tslib_content.php</code>?</p></li>
  </ol>