title: Finding non-expiring keys in Redis
body: <p>In my setup, the <code>info</code> command shows me the following:</p>
  
  <pre><code>[keys] =&gt; 1128
  [expires] =&gt; 1125
  </code></pre>
  
  <p>I'd like to find those 3 keys without an expiration date. I've already checked the docs to no avail. Any ideas?</p>