title: X-PHP-Response-Code Headers
body: <p>I saw this header(X-PHP-Response-Code) here in this SO <a href="https://stackoverflow.com/a/12018482/1747193">answer</a> and was wondering.</p>
  
  <ol>
  <li>What is the function and are there any other X-PHP-* headers?</li>
  <li>If there are what is their function and usage (as much info as possible)?</li>
  <li>If this is the only one (in which I doubt) ignore 2.</li>
  </ol>