title: extracting from a tar file with duplicate entry names
body: <p>If you add the same file to a tar file multiple times, and then extract that file, are you guaranteed that the extracted version is equivalent to the one which was last added?</p>
  
  <pre><code>~/tmp&gt; echo hi &gt; foo
  ~/tmp&gt; tar -cf bar.tar foo
  ~/tmp&gt; echo bye &gt; foo
  ~/tmp&gt; tar -uf bar.tar foo 
  ~/tmp&gt; tar -tf bar.tar
  foo
  foo
  ~/tmp&gt; rm foo
  ~/tmp&gt; tar -xf bar.tar foo
  ~/tmp&gt; cat foo
  bye
  </code></pre>
  
  <p>It make sense that it would, but I can't find any documentation to that effect.   I'm wondering if anyone in the know might know, or if someone knows a circumstance where this is not true?</p>