svn commit: r216823 - head/sbin/shutdown

[Alexander Best]

On Fri Dec 31 10, Erik Trulsson wrote:
> On Fri, Dec 31, 2010 at 07:00:58PM +0000, Alexander Best wrote:
> 
> [snip]
> 
> > another thought: running 'reboot' instead of 'shutdown -r now' *can* cause
> > harm to the system, because an important rc.shutdown script wasn't executed.
> > however running 'shutdown -r now' in single-user mode e.g. will cause a few
> > sterr warnings; however it *cannot* cause any harm.
> 
> Oh, yes, it can! (And I have been burnt by it once, after which I got
> very careful about not using 'shutdown -r now' from single user mode.)
> 
> Take a look at /etc/rc.d/mixer
> At shutdown it saves the current state of the soundcard mixer values
> into a file and at start it restores the mixer values from that file.
> If you boot into single user mode the start function will of course not
> be executed leaving the mixer values at their default values.  If you
> then use 'shutdown' these default values are what will be saved,
> overwriting whatever values had been saved before, while if you had
> instead had used 'reboot' the old saved values would have been left
> untouched.
> If you never change the mixer values from their defaukt you won't notice
> anything, but otherwise it might take a while to figure out why the
> sound is at the 'wrong' volume.
> 
> This is one example I have found where bad things can happen if you use
> 'shutdown' when you should have used 'reboot'.  I am fairly sure that
> there are other instances that I just haven't run into (yet.)

that's a very good argument and in fact i remember to have also once been
bitten by the 'mixer' case.

so after a some more thoughts: just leave it the way it is. it would be nice
to have two commands which would do 'shutdown -r now' and 'shutdown -h now',
but i can't think of a name: slowboot/slowhalt? ;)

cheers.
alex

> 
> 
> 
> 
> -- 
> <Insert your favourite quote here.>
> Erik Trulsson
> ertr1013 at student.uu.se

-- 
a13x