Re: suspend questions

[Steven Bellovin <smb%cs.columbia.edu@localhost>]

On Jul 16, 2009, at 10:16 AM, Jeremy C. Reed wrote:

> On Thu, 16 Jul 2009, Goran wrote:
>
> > > I read that I may need to run vbetool to turn my display back on.  
> > > How do I
> > > trigger that? I have powerd running ... any sensor/trigger to  
> > > identify the
> > > unsuspend?
> > >
> > > Also I don't even know how to unsuspend. Just press power button?
> > > Open laptop lid?
> >
> > On Dell Latitude Plattform you can press the power button (if lid is
> > opened) or open the lid (if lid is closed). If you're using a docking
> > stations power button (and/or dell-monitor-stand power button) the  
> > lid
> > can stay closed (in conjunction with an external monitor).
>
> Thanks.
>
> I already use a powerd script to handle the power button to do a  
> shutdown.
> Do I need to disable that. I am unclear whether this means that powerd
> will also run the sleep_button script after my power_button script.  
> Or I
> can just rewrite my power_button script to do something to suspend.

I think that that's more a BIOS issue -- it decides what to do with  
the power switch.  At least, I've seen that in several different
BIOSes, and on my Thinkpad it can wake from suspend or initiate a  
shutdown if I press it when the machine is awake.
> I also already use powerd script lid_switch to run "vbetool dpms on"  
> to
> turn my display back on when released. Any sysctls I should also be  
> using?

Not that I know of -- when the sysctl call to write to sleep_state  
returns, the machine has awakened from suspension, so it does the  
wakeup activities.

> (Sorry I just can't find any docs about this.)
>
> Where is the machdep.sleep_state sysctl tunable documented?
>
> Thanks for your info...