6.x acpi powerbutton

[Nate Lawson]

Ian Smith wrote:
> On Fri, 10 Apr 2009, Nate Lawson wrote:
>  > Andriy Gapon wrote:
>  > > on 09/04/2009 23:24 Stephen Clark said the following:
>  > >> Is there a reason it doesn't send and event like Linux that can be acted
>  > >> upon by user space other
>  > >> than signaling init? I like to have a message written in
>  > >> /var/log/messages that someone pressed
>  > >> the powerbutton.
>  > > 
>  > > I think that for all suspend states except S5 userland is notified via
>  > > devd mechanism and potentially can veto the suspend. S5 (soft-off) is
>  > > coded to start shutdown immediately. You can try to hack on
>  > > acpi_ReqSleepState in sys/dev/acpica/acpi.c.
>  > > 
>  > > I am not sure what is the reason for this special behavior of S5. But I
>  > > like it, because it sometimes allows me to perform semi-clean shutdown
>  > > when X goes crazy. But I also see when it could be useful to have S5
>  > > request go through userland. So this could be configurable.
>  > 
>  > The reason for userland getting into the loop in the first place was to
>  > run programs to shut down devices and reinit them after resume. This
>  > isn't necessary in the shutdown case because init already sends a
>  > signal, as you mention.
>  > 
>  > There's already a mechanism for timing out if userland is not
>  > responding, so a suspend will ultimately happen whether or not it
>  > answers. However, that waits for a while (1 minute?) and devd used to be
>  > optional, so I thought it best to keep the existing S5 behavior
>  > (immediate shutdown).
>  > 
>  > It may be ok to enable this for S5 but I don't think it's very useful.
> 
> Perhaps a silly question, but is it too late at this stage of the game 
> to try logging S5 events to syslog before dying?  I agree with Stephen, 
> logging 'shutdown by powerbutton' surely beats what might otherwise 
> resemble a spontaneous reboot?  Or is something already logged here?

I'm not resisting this, but I'm having trouble seeing the importance.
What happens differently than if someone hits CTRL-ALT-DEL on a virtual
console?

-- 
Nate