title: Interesting usage of tar... but what is happening?
body: <p>I saw the following interesting usage of tar in a co-worker's Bash scripts:</p>
  
  <pre><code>`tar cf - * | (cd &lt;dest&gt; ; tar xf - )`
  </code></pre>
  
  <p>Apparently it works much like rsync -av does, but faster.  The question arises, how?</p>
  
  <p>-m</p>
  
  <hr>
  
  <p><strong>EDIT</strong>: Can anyone explain <em>why</em> should this solution be preferable over the following? </p>
  
  <pre><code>cp -rfp * dest
  </code></pre>
  
  <p>Is the former faster?</p>