title: Modifying files nested in tar archive
body: <p>I am trying to do a <code>grep</code> and then a <code>sed</code> to search for specific strings inside files, which are inside multiple tars, all inside one master tar archive. Right now, I modify the files by</p>
  
  <ol>
  <li>First extracting the master tar archive.</li>
  <li>Then extracting all the tars inside it.</li>
  <li>Then doing a recursive <code>grep</code> and then <code>sed</code> to replace a specific string in files.</li>
  <li>Finally packaging everything again into tar archives, and all the archives inside the master archive.</li>
  </ol>
  
  <p>Pretty tedious. How do I do this automatically using shell scripting?</p>