title: How do I prepend a string to each line in a text file using Windows cmd?
body: <p>I have a long list where each line reads</p>
  
  <pre><code>p1 Title 1
  p24 Title 2
  p84 Title 3
  ...
  </code></pre>
  
  <p>I need each file to be prepended with a simple string, the initials of the book like so.</p>
  
  <pre><code>MB.p1 Title 1
  MB.p24 Title 2
  MB.p84 Title 3
  ...
  </code></pre>
  
  <p>I have tried the tips on <a href="https://stackoverflow.com/questions/10021464/batch-file-to-add-characters-to-beginning-and-end-of-each-line-in-txt-file">Batch file to add characters to beginning and end of each line in txt file</a> and <a href="https://stackoverflow.com/questions/155932/how-do-you-loop-through-each-line-in-a-text-file-using-a-windows-batch-file#">How do you loop through each line in a text file using a windows batch file?</a></p>