Utility to control the starting, stopping, and restarting of system services. The services that can be affected are described in the /Library/StartupItems and /System/Library/StartupItems/ paths.
The action and service arguments are optional. If no service argument is specified, all startup items will be affected. When a specific startup item is given, that item and all the items on which it depends, or that are dependent on it, will be affected.
Currently, rc calls SystemStarter at boot time. Because SystemStarter may eventually take over the role of rc, it's advisable to create custom startup items rather than continue to modify rc.
Safe mode startup (a basic startup that only runs Apple items).
Keep running after last startup item completes (in graphical startup only).
Print debugging output.
Print debugging output and shows dependencies.
Quiet mode that silences debugging output.
A pretend run mode that doesn't actually perform actions on any items.