The default, causing the system to reboot in its usual fashion. The
admin_data field points to an implementation defined string
that specifies the system image to reboot.
ADMIN_HALT
The system is simply halted; no reboot takes place.
ADMIN_FAST
The system does no send SIGTERM to active processes before halting.
ADMIN_IMMEDIATE
The system does not perform any of the normal shutdown procedures.
ADMIN_ALTSYSTEM
The system reboots using the admin_data string as a specification
of the system to be booted.
ADMIN_ALTCONFIG
The system reboots using the admin_data string as a specification
of the initial implicit configuration space.
ADMIN_SYSDUMP
Dump kernal memory before rebooting.
ADMIN_INIT
An option allowing the specification of an alternate initial program
to be run when the system reboots.