title: Shell script to compare dates from multiple files in Linux
body: <p>I have lots of home directories under /ifshome on Linux. I want to see which users have not logged in for the past 6 months, and my solution is to parse the /ifshome/user/.lastlogin file. Each .lastlogin file has the same format, 1 line:</p>
  
  <pre><code>Last Login: Fri Mar 09 18:06:27 PST 2001
  </code></pre>
  
  <p>I need to build a shell script that can parse the .lastlogin file in each user's home directory and output those directories whose owners haven't logged in for the last 6 months. </p>