title: create tar file from some .tar.gz file
body: <p>I would like to create a <code>.tar</code> file from all <code>.gz</code> files in <code>$a/$b</code> and delete those files afterwards.</p>
  
  <p>I have come up with the following code but it's not working:</p>
  
  <pre><code>cd "$a"
  #tar cf $a/$b'.tar' "$b_sql.gz" "$b_moh.tar.gz" 
  tar cf $a/$b'.tar' $b'_*.gz'
  gzip $a/$b'.tar'
  rm -f $b'_*.gz'
  </code></pre>