From: wolff@dutecai.et.tudelft.nl (Rogier Wolff) Subject: Re: ctrl-alt-del doesn't reboot Date: 13 Feb 1992 15:09:06 GMT
comrade@uniwa.uwa.oz.au (Peter Cooper) writes:
> [someone writes]:
>:
>: As a side note, how difficult would it be to have ctrl-alt-del do a
>: sync before rebooting? Perhaps a hard-core Unix hacker is comfortable
>: with explicit syncs, but I find it a little crude.
>Main problem here is that (This is hersey, correct if I am wrong) sync()
>only schedules the buffers for writing, and the buffers may not
>nesserily be actually written when sync() returns.
Some people will argue that you may want to reboot a malfunctioning
system which you realize has just corrupted your superblock. In this
case you DO NOT want to sync the disks before rebooting.
SunOS does this by doing
for (i=10,n=1;(i>0) && (n > 0);i--)
{
sync ();
printf ("%d ",n=number_of_unflushed_buffers ());
sleep (1);
}
This is quite effective. If possible the system will write the disks, and
continue shutdown within a second. Max timeout is about a second.
Be careful with sync() and sleep() in kernel/interrupt routines.
Roger
--
If the opposite of "pro" is "con", what is the opposite of "progress"?
(stolen from kadokev@iitvax ==? technews@iitmax.iit.edu)
EMail: wolff@duteca.et.tudelft.nl ** Tel +31-15-783644 or +31-15-142371