Re: NetworkManager and suspend

[Dan Williams <dcbw redhat com>]

On Thu, 2005-02-03 at 21:08 +0100, Rene Rask wrote:
> Is NetworkManager able to detect changes in state like S3/S4/S5 and
> recover from it? or should I edit my suspend script and restart

Nope, NM is blissfully unaware of power management right now, which is
wrong.  I haven't had time to look at it though.  Interestingly enough,
what usually happens in the suspend scripts that people have is that
they 'rmmod airo' or 'rmmod ee1000'.  That signals HAL that the driver
is gone, and it will then signal NetworkManager that to remove that
device from its list.  When you wake up, the scripts commonly have
'modprobe airo' or whatever and that makes HAL signal NM of a new
device.  In any case, if the driver supports sleep I don't think this
dance is necessary, and NetworkManager doesn't deal wtih that case yet.

> I must admit I have no idea if hal and dbus are usable for acpi stuff.

HAL is just now getting ACPI/APM support so that it knows the states of
various buttons and such.  I'm not sure how user applications figure out
when the system goes to sleep or when it wakes up though.
NetworkManager will definitely need to intercept these signals (whether
they come from elsewhere or eventually from HAL or a 'power daemon' of
some sort) and shut down all devices, then bring them back up on wake.

I'd imagine that when NM got a "sleep" signal from wherever, it would
close all file descriptors related to that device, turn the device off
(ie mark it as 'down'), and then wait until it gets the "awake" signal
before starting things back up again.  That code needs to be done.

Dan