title: PHP Global variables for an externally included, AJAX loaded PHP file
body: <p>Is it possible to access a Global variable declared in a file, e.g. a <code>header.php</code> file, from another external PHP file named <code>content.php</code> that has been loaded with an AJAX call, without using GET or POST? </p>
  
  <p>e.g.</p>
  
  <p>index.php:</p>
  
  <pre><code>&lt;?php
  
      include 'header.php'; //The global variable $SESSIONID is defined in this file
  
      echo '&lt;div id="for-content"&gt;&lt;/div&gt;';
  
      include 'footer.php';
  ?&gt;
  </code></pre>
  
  <p>header.php</p>
  
  <pre><code>&lt;?php
      $SESSIONID = "asdf";
  ?&gt;
  </code></pre>
  
  <p>content.php:</p>
  
  <pre><code>&lt;?php
      echo $SESSIONID;
  ?&gt;
  </code></pre>
  
  <p>And the AJAX call:</p>
  
  <pre><code>$("#for-content").load("content.php");
  </code></pre>