title: Regex to find some .php files
body: <p>I'm trying to make an exclusion regex for a crawler. I want to index all the <code>.php</code> files that appear in the <code>/archives/</code> directory, but not anywhere else. So the regex should match all <code>.php</code> files, except those that are in an <code>/archives/</code> directory (however deeply nested).  So, for example, it will index </p>
  
  <pre><code>www.mysite.com/archives/123qwe/index.php 
  </code></pre>
  
  <p>but not </p>
  
  <pre><code>www.mysite.com/123qwe/index.php
  </code></pre>
  
  <p>I believe this regex should work: <code>(?&lt;!\/archives\/.*)\.php$</code></p>
  
  <p>However, I'm not able to use the <code>&lt;</code> character, because I need to submit the regex into a web form that sanitizes <code>&lt;</code>'s from the input. And using <code>&amp;lt;</code> breaks the regex. So is there another way to form this regex, without needing the <code>&lt;</code>?</p>