A rule it's a minimal set of conditions to be met to write an entry to a logfile. You must add valid rules before starting the engine.
Once started, the engine will check events every x seconds (specified using interval argument) and for every registry (System, Application, Security, Installation or a user defined one) that is requested at least in one rule will check for an event's source specified and optionally for some text contained in the event's description.
If the rule it's succesfull then an entry it's wrote in the specified logfile. A custom callback can transofrm the line to be wrote using the format option. The parser can optionally shutdown itself if endtime it is specified.