# shutdown --help
shutdown: invalid option -- -
Usage: shutdown [-akrhfnc] [-t secs] time [warning message]
-a: use /etc/shutdown.allow
-k: don't really shutdown, only warn.
-r: reboot after shutdown.
-h: halt after shutdown.
-f: do a 'fast' reboot (skip fsck).
-F: Force fsck on reboot.
-n: do not go through "init" but go down real fast.
-c: cancel a running shutdown.
-t secs: delay between warning and kill signal.
** the "time" argument is mandatory! (try "now") **
# halt --help
usage: halt [-n] [-w] [-d] [-f] [-i] [-p]
-n: don't sync before halting the system
-w: only write a wtmp reboot record and exit.
-d: don't write a wtmp record.
-f: force halt/reboot, don't call shutdown.
-p: power down the system (if possible, otherwise halt)
Т.е. shutdown тут тебе не поможет - используй halt.
init-скрипт halt к команде halt отношения не имеет. Команда сама по себе, а скрипт может ее вызвать.
