There’s a number of tricks people use when profiling and debugging UNIX daemons.
The problem with a daemon is that it’s not generally connected to a user interface. It sits there in the background accepting requests through some communications medium, and sending responses back. By its very design, it’s meant to get out of the way and be unobtrusive.
So when you are trying to find out what a daemon is doing, in order to test it or to diagnose a problem, tricks are required.
