Sergey Udaltsov sergey.udaltsov at
Mon Dec 13 16:50:46 PST 2004


Just some general thoughs regarding addons and related properties
(just some food for thought, very far from beeing considered as an
attempt to specify something).

I think, there should be some different policies for the addons
invocation and termination. Possible evident variants:

- Launch the instance of addon for every attached device - and kill
(sending probably SIGUSR1?) on the device unplug.

- Launch the instance of the addon for the first device within some
group - and kill once the last member of the group is unplugged (is it
useful in any way?)

- Launch single, per-system, instance of the addon once first device
is plugged (requiring this addon) - and killing when the last is gone

- Start on hald startup, stop on hald shutdown.

Probably, there can be other variants, combinations. So what I see
here is three properties:

- (string) - the path to the binary executable
- (string) - one of the predefined policyt names
- (string) - optional, the name of the group

The policies should be supported by the hald and libhal - so minimal
coding on the addon side is required. I think manually coding these
things in each addon is not a WTG.


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