Autosave D-BUS message?

[David Zeuthen]

On Tue, 2005-06-28 at 19:08 -0400, John (J5) Palmieri wrote:
> On Mon, 2005-06-27 at 14:25 -0700, Sean Meiners wrote:
> > We (Linspire) are actually planning on having the hibernation scripts generate 
> > a signal on the system bus that announces that the system is going to sleep.  
> > This way any application who cares (we had only thought of network apps like 
> > Gaim & Mozilla so far) can 'prepare' themselves properly.  I wasn't planing 
> > on hashing out the details for some time yet, but since is looks like we're 
> > not the only ones thinking about this it would make sence to lay out the 
> > object/path/signal(s) now so that we're all compatible.
> 
> I think davidz was doing stuff for this in HAL.  It knows when the lid
> is closed or the user has pressed the suspend button so it would be nice
> to have HAL send those signals.

You see, this is a little bit different as in HAL just provides the bits
to tell you when events happen - if you wanted you could just write some
ACPI scripts that fires of signals :-)

So to solve the original problem you really want something that enforces
policy though - I wrote about this here (search for REQUIREMENTS FOR THE
PROGRAMMATIC INTERFACE)

 URL: http://mail.gnome.org/archives/utopia-list/2005-April/msg00002.html
 Google Cache:  http://64.233.161.104/search?biw=925&hl=en&q=cache%3Ahttp%3A%2F%2Fmail.gnome.org%2Farchives%2Futopia-list%2F2005-April%2Fmsg00002.html&btnG=Google+Search
 (the GNOME servers are currently down)

It is my view that to do this the right way you really need all the
veto / timeout stuff (just emitting a signal as Sean proposes is not
enough e.g. my IM or email client may take e.g. 10 seconds to
synchronize and close connections) though keep in mind the proposal
linked to is only a rough first sketch. 

You also want this on the session bus rather than the system bus to cope
with the remote application scenario (and in that particular scenario we
probably want to tunnel D-BUS over X but that is another discussion).

    David