title: Append one line at the top of huge gzip file
body: <p>I have a huge gzip file (~400MB). I want to append one line of text at the BEGINNING of the file.</p>
  
  <p>I was thinking of creating a gzip file with the header line and then using <code>zcat</code> to combine header file and log file. Just wanted to check if there is a better/elegant/efficient way to do it.</p>