[RFC] add a shutdown event

[Hardening]

On 17/03/2013 23:59, Sylvain BERTRAND wrote:
> On Sun, Mar 17, 2013 at 11:32:21PM +0100, Hardening wrote:
>> This patch adds a shutdow event so that clients can be notified
>> when the compositor is about to exit (and potentially kill its
>> child processes). 
>> This patch is based on gh next.
> 
> Is the socket disconnect not enough information for the clients?
> 
As most of the time the compositor launched all the wayland clients,
they may be killed before they discover the socket has disconnected.

It can be seen as a "hurry to cleanup before being killed" message.

Probably most of the client won't implement the callback but the one
that care will be able to.