title: Is it possible to resume 7zip compression?
body: <p>My application regularly upload large files. Regardless of their size, all files are compressed before uploaded to server.</p>
  
  <p>Part of this project requirements is to resume nicely after crash/power failure, so right now compression is done this way:</p>
  
  <ul>
  <li><strong>large-file.bin</strong> sliced in N slices</li>
  <li>Compress each slice &amp; upload it</li>
  </ul>
  
  <p>In case of crash, I pickup from the last slice.</p>
  
  <p>To optimize upload speed, I'm currently looking into sending the whole file (uploads are resumed if failed) instead of sending slices one by one, so I'm looking into compressing the whole file instead of compressing each slice.</p>
  
  <p>I'm currently using <strong>7z.dll</strong>. I wonder if it's possible, in case of power failure, to tell 7z to <em>resume</em> compression.</p>
  
  <p>I know I could always implement my own compression routine and implement such feature, but <strong>before</strong> going that road I wonder if it's possible to do that in 7z (which already have an excellent compression ratio)</p>