most modern cron jobs are wrapped in a script that does some basic housekeeping, e.g. making sure not attached to terminal, create a .pid file, and generate a proper timestamp entry in syslog for the process start and end, like "PID process_name started YYYYMMDD HH:MM:SS" and corresponding process terminate stamp. In any case, you could set this up if desired..as I think it's a bit more robust than processing process polling output/log.