Re: New modules in 2.14

[Richard Hughes <hughsient gmail com>]

On Thu, 2006-01-19 at 14:19 +0800, James Henstridge wrote:
<snip> 
> This always seemed a bit weird to me.  Is there any reason to choose
> this form of integration.
> 
> Wouldn't it have been better to make gnome-screensaver listen for the
> HAL power management events directly, and lock the screen/throttle the
> screensaver where appropriate?

gnome-screensaver is just that, a screensaver with a defined dbus
interface. gnome-power-manager does all the policy decisions, which
include what to notify on suspend, resume etc.

> Similarly, why does gnome-screensaver need to ask gnome-power-manager to
> power down the screen?  Isn't this a simple X call that it could do itself?

It used to (I'm not sure what mode is enabled in cvs g-s), but it was
not seen proper for a screensaver daemon to control the low level power
management of a screen. Logically why should it? I know XScreenSaver had
this feature, but that's all legacy stuff now.

> I guess the main question is: why would an app use the
> gnome-power-manager interfaces to respond to power management events
> rather than HAL's notifications?

Not quite sure what you mean? You mean about the registering for
notification stuff? That part is in heavy discussion at the moment from
lots of developers, and nothing is in CVS yet. Currently g-p-m hardcodes
the events that happen on suspend, such as notifying NetworkManager and
g-s over dbus.

Richard.