Being interested in NameOwnerChanged for a namespace, not one name

[Will Thompson]

Hi folks,

On 20/09/10 02:18, Marcel Holtmann wrote:
> However this is not true for Telepathy. They have the central registrar
> service which is called Mission Control. And that is required to always
> be running. So the active registration would make sense here.

Actually, there are situations where it makes sense to use Telepathy 
connection managers without Mission Control. (For example, Fargo 
<http://telepathy.freedesktop.org/wiki/Fargo> uses telepathy-sofiasip 
directly, since there's no need to track accounts or dispatch channels 
to one of a number of different clients.) So, we cannot make connection 
managers actively register with Mission Control.

One alternative would be to make connection managers emit a Hello() 
signal when they start; if MC happened to be running, it could listen to 
that signal. But as Lennart says, Telepathy is not the only framework 
using this pattern; if we can address this problem with it once and for 
all in D-Bus itself, then I think we should, rather than every 
similarly-shaped framework reinventing registration.

 From an earlier mail, about whether globbing is useful:

> for the bus name, maybe not. For the object path, it might makes sense.

I note that D-Bus already has support for matching object paths (which 
are a distinct type from strings, so arg0 matching—and arg0prefix 
matching, in my implementation—don't work on them). The semantics are 
actually kind of sketchy: the patch specified in the rule matches any 
path of which it's a prefix, or which is a prefix of it! I wonder why it 
was made symmetrical like that.

Happy Monday,
-- 
Will