title: ffmpeg 2 pass encoding on aws Lamba
body: <p>I'm doing a 2 pass encoding with ffmpeg on AWS Lambda. Ffmpeg needs to create a temporary log file on first pass, that is used on the second pass.</p>
  
  <p>Since Lambda allows write operations only in "/tmp/", I get the following expected error:</p>
  
  <pre><code>Cannot write log file 'ffmpeg2pass-0.log' for pass-1 encoding: Read-only file system
  </code></pre>
  
  <p>How can I force ffmpeg to write the log file in a specific directory ? -passlogfile doesn't seem to do the trick.</p>