[PATCH] Shutdown cooloff feature

[Matthew Seaman]

Aristedes Maniatis wrote:

> Why would an operating system have an unclean shutdown command at all? 

reboot(8) by default isn't a completely unclean shutdown.  It does flush
any pending IO to disk and send a SIGTERM to all processes which should 
stop them relatively cleanly and get you back up again without having to
fsck(8) everything.  What it doesn't do is run the rc.subr(8) shutdown
scripts.  A lot of the time, you'ld get away with that.  It's only if
you've got apps that don't handle SIGTERM correctly, or that take too
long shutting down and get zapped by the SIGKILL reboot(8) sends
to the laggards.  (A big RDBMS for instance)

If you want a really unclean shutdown, try 'reboot -q' or 'reboot -n'.
'reboot -qn' is virtually the same as toggling the power off and on again
at the mains.  Hmmm... didn't there use to be a note about using 'halt -n'
"if the processor catches fire" in the reboot(8) man page?

	Cheers,

	Matthew

-- 
Dr Matthew J Seaman MA, D.Phil.                   7 Priory Courtyard
                                                  Flat 3
PGP: http://www.infracaninophile.co.uk/pgpkey     Ramsgate
                                                  Kent, CT11 9PW

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 259 bytes
Desc: OpenPGP digital signature
Url : http://lists.freebsd.org/pipermail/freebsd-current/attachments/20100103/c0badb75/signature.pgp