title: CodeIgniter redirect 503
body: <p>I wanted to set a maintenance page for my website.</p>
  <p>To do so, I check a field in the DB, in the first script running (MY_Controller). If it's on maintenance, I would like to redirect the user to the maintenance page. This works:</p>
  <pre><code>redirect(&quot;maintenance&quot;, 'location');
  </code></pre>
  <p>Here is my issue. I want to set the header code to 503 in order to avoid bots indexing the maintenance page in place of the real one. But whenever I do this:</p>
  <pre><code>redirect(&quot;maintenance&quot;, 'location', 503);
  </code></pre>
  <p>The maintenance page doesn't load, the URL doesn't change.</p>