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HALT

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
DIAGNOSTICS
NOTES
AUTHOR
SEE ALSO

NAME

halt, reboot, poweroff ? stop the system.

SYNOPSIS

/sbin/halt [?n] [?w] [?d] [?f] [?i] [?p]
/sbin/reboot
[?n] [?w] [?d] [?f] [?i]
/sbin/poweroff
[?n] [?w] [?d] [?f] [?i]

DESCRIPTION

Halt notes that the system is being brought down in the file /var/log/wtmp, and then either tells the kernel to halt, reboot or poweroff the system. If halt or reboot is called when the system is not in runlevel 0 or 6, shutdown(8) will be invoked instead (with the flag -h or -r).

OPTIONS

?n

Don’t sync before reboot or halt.

?w

Don’t actually reboot or halt but only write the wtmp record (in the /var/log/wtmp file).

?d

Don’t write the wtmp record. The ?n flag implies ?d.

?f

Force halt or reboot, don’t call shutdown(8).

?i

Shut down all network interfaces just before halt or reboot.

?p

When halting the system, do a poweroff. This is the default when halt is called as poweroff.

DIAGNOSTICS

If you’re not the superuser, you will get the message ‘must be superuser’.

NOTES

Under older sysvinit releases , reboot and halt should never be called directly. From release 2.74 on halt and reboot invoke shutdown(8) if the system is not in runlevel 0 or 6. This means that if halt or reboot cannot find out the current runlevel (for example, when /var/run/utmp hasn’t been initialized correctly) shutdown will be called, which might not be what you want. Use the -f flag if you want to do a hard halt or reboot.

AUTHOR

Miquel van Smoorenburg, miquels@cistron.nl

SEE ALSO

shutdown(8), init(1)


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