Re: Moving to bonjour over howl

[Alexander Larsson <alexl redhat com>]

On Fri, 2005-09-16 at 23:33 +0800, Davyd Madeley wrote:
> On Fri, 2005-09-16 at 17:17 +0200, Alexander Larsson wrote:
> 
> > I'm not saying Avahi needs a mainloop. However, GServiceBrowser clearly
> > needs one. Anyway, I was just explaining why the gnome-vfs dns-sd code
> > looks like it does. It seemed like David just looked at it and said
> > "ewww, this is ugly, I'll do my own thing instead" without an
> > understanding of why it looks like it does.
> 
> It is currently designed to handle a more generic case.
> 
> I am not sure why the DNS-SD code has to necessarily be able to handle
> synchronous and asynchronous calls. Shouldn't gnome-vfs-daemon simply be
> tracking devices on the network which are then offered in some logic way
> back to the gnome-vfs API?

How do you implement the commandline call "gnomevfs-ls network:///"
which does a synchronous gnome-vfs readdir call, that will return
results from a dns-sd call, with an asynchronous dns-sd call? 

Also, I'm not sure why you brought up the vfs daemon here. Howl already
has a daemon, and that daemon is doing all mDNS work, including caching
all mDNS state from things that has been seen on the network.

> It seemed to me at the moment that Howl gets stopped and started a lot,
> which would either cause sporadic blasts of network traffic or cause
> events to be missed. I'm not sure which. Please correct me if I've
> understood it entirely wrong.

Started and stopped? The Howl daemon runs all the time, and it caches
the current state of all mDNS records in the local network (as long as
their TTL specifies). Then all howl clients (such as e.g. gnome-vfs) ask
the daemon for data, and most of the time the howl daemon can
immediately reply. There are no events missed, and there is no
unnecessary traffic.

Doesn't avahi work like this? mDNS really was designed to have a
system-wide daemon that does all the querying and caching, otherwise you
can easily end up with way to much network traffic.

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Alexander Larsson                                            Red Hat, Inc 
                   alexl redhat com    alla lysator liu se 
He's a deeply religious crooked dog-catcher on a search for his missing 
sister. She's a chain-smoking nymphomaniac mercenary looking for love in all 
the wrong places. They fight crime!