title: Recursive git update-index --assume-unchanged
body: <p>I'm trying to run the following:</p>
  
  <pre><code>git update-index --assume-unchanged myFolderToIgnore
  </code></pre>
  
  <p>Where <code>myFolderToIgnore</code> is a folder.  However it fails saying its "unable to mark" it.</p>
  
  <p>So I tried:</p>
  
  <pre><code>git update-index --assume-unchanged myFolderToIgnore/
  </code></pre>
  
  <p>Which GIT responds to with <code>Ignoring path myFolderToIgnore/</code> but doesn't do anything (it still sees my changes and tries to check them in).</p>
  
  <p>In the end I had to go in and manually mark each individual file as unchanged.  What am I missing here?</p>