title: File handles in Perl
body: <p>Instead of the typical file handle I am used to:</p>
  
  <pre><code>open INPUT, $input;
  while ($line = &lt;INPUT&gt;) {
      ....
  }
  close INPUT;
  </code></pre>
  
  <p>How do I retrieve a pointer to the line in a file so that I can advance these pointers at wiil? I'm trying to create two pointers to their corresponding <em>sorted</em> files so that I can advance pointers based on whether the line in one file is "less" or "greater" than the line in the other.</p>
  
  <p>Note: Assume input files are BIG.</p>