fcgi-debug helps you to trace what happens with your fastcgi programs without having to strace them;
it just sits between webserver and your fastcgi program and forwards all content while analysing it.

Build Requires:
  glib2
  libev
  cmake

For running you probably want spawn-fcgi (either from lighttpd, or from https://cgit.stbuehler.de/gitosis/spawn-fcgi/about/)

Example usage (assuming the binary is in build/fcgi-debug, starts a fastcgi server listening on port 1026):

  spawn-fcgi -C 0 -p 1026 -n -- build/fcgi-debug /usr/bin/php5-cgi