title: How to perform grep operation on all files in a directory?
body: <p>Working with xenserver, and I want to perform a command on each file that is in a directory, grepping some stuff out of the output of the command and appending it in a file.</p>
  
  <p>I'm clear on the command I want to use and how to grep out string(s) as needed.</p>
  
  <p>But what I'm not clear on is how do I have it perform this command on each file, going to the next, until no more files are found.</p>