title: How to list filenames with regular expression
body: <p>I have multiple files with different suffix:</p>
  
  <pre><code>file_12
  file_34
  file_1245
  file_4567
  file_4
  </code></pre>
  
  <p>I only want to list the files whose suffix has four digits. I know I could do it like </p>
  
  <pre><code>ls -l file_[0-9][0-9][0-9][0-9]
  </code></pre>
  
  <p>But is there a better way to do it?</p>