title: UNIX - grep files based on permission
body: <p>I have a very specific request. I have a directory with a lot of files, all with varying permissions. </p>
  
  <p>I want to identify all files that any user (user group other) can read, but I need to use grep. (I know there is better ways than grep but this is a special request)</p>
  
  <p>My directory name is <code>testfiles</code>. I am thinking along the following lines:</p>
  
  <pre><code>ls /testfiles | grep -E &lt;&lt;insert more&gt;&gt;
  </code></pre>
  
  <p>Can someone advise me?</p>