Subject: Re: ACPI userland issues
To: Jared D. McNeill <jmcneill@invisible.ca>
From: Steven M. Bellovin <smb@cs.columbia.edu>
List: current-users
Date: 06/20/2006 14:47:34
On Tue, 20 Jun 2006 15:27:49 -0300 (ADT), "Jared D. McNeill"
<jmcneill@invisible.ca> wrote:

> On Tue, 20 Jun 2006, Steven M. Bellovin wrote:
> > I do have some issues involving the user interface, though.
> >
> > suspend/resume scripts
> > 	 There don't seem to be any.  I do a lot in my /etc/apm/suspend
> > 	 and resume scripts; acpi needs that ability
> 
> This is what powerd(8) is for. Scripts are run from /etc/powerd/scripts/, 
> the man page has more details.

Understood -- but the man page says nothing about suspend/resume scripts
for powerd.  Are such scripts supported?

> > other states
> > 	Do we support other ACPI states?  Are we going to?  Standby
> > 	is nice...
> 
> S1 should "just work", but you need to manually shut off your backlight in 
> most cases.

Is a script run for this?  That is, can I have a script that turns off
the backlight?  Do I need to do anything on transitions back to S0, such
as turning the light back on?
> 
> > lid open
> > 	What does acpi do on a lid open event?  Yes, there's a
> > 	script -- but how does the script run if the machine is
> > 	still in state 3? If it's not in state 3 at that time, is
> > 	there a purpose to the script?  On my T42, I can suspend
> > 	with the proper sysctl, and wake up by hitting the Fn key.
> > 	If I suspend and close the lid, though, opening it doesn't
> > 	wake the machine up.  I haven't tried writing a lid_switch
> > 	script that will do the sysctl when I close the lid, to
> > 	see if that makes for useful behavior when I open it.
> 
> Depends on the hardware. My vaio delivers a "lid open" event on resume, 
> which will trigger powerd to run the lid_switch script. My Dell, on the 
> other hand, requires you to wake up by pressing the power button, so I 
> need to handle this in the wakeup script.
> 
Under apm, opening my lid resumes the machine.  Do I need a lid_open
switch to do something now?  If so, what?  What does your wakeup script do?


		--Steven M. Bellovin, http://www.cs.columbia.edu/~smb