Re: [PATCH v2] Autoconnect jack ports by default

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

On Donnerstag, 25. Februar 2021 09:48:55 CET Gerd Hoffmann wrote:
> On Wed, Feb 24, 2021 at 11:33:14PM +0100, Christian Schoenebeck wrote:
> > On Mittwoch, 24. Februar 2021 23:04:47 CET Geoffrey McRae wrote:
> > > This goes against how all standard jack clients work, a new jack client
> > > should not auto-connect at all unless explicitly configured to as if
> > > there is an existing audio diagram configured (which is 99% of the time)
> > > it will cause unexpected/undesired behavior.
> > > 
> > > Jack is not supposed to be an 'automatic' system, it's the
> > > responsibility of the patch bay software to route connections.
> > > 
> > > The auto-connect feature exists to allow the jack audiodev to re-connect
> > > a broken connection when the jack device restarts/reconnects.
> > 
> > Well, that was also my idea first, and I would agree with you in case of a
> > regular music app of course, but then I thought QEMU is probably not an
> > average JACK client, and it simply lowers the entry level for new users
> > who
> > probably just want to output to system out anyway.
> 
> Well, I guess there is more software like that, any music player for
> example.  I don't think this is a good reason for qemu to have
> non-standard behavior.  If you want qemu autoconnect, you can use the
> connect-ports option.
> 
> Beside that I'd expect the patch bay software is able to remember the
> routing configuration per application, so the setup would be a one-time
> thing you don't have to re-do on every qemu launch.  Not fully sure this
> is actually the case though, I'm not a regular jack user.
> 
> take care,
>   Gerd

Yes, a JACK client with patchbay functionality like QJackCtl stores and 
restores individual connections. You need to start it each time for doing that 
though.

JACK clients with consumer purpose often auto connect to system ports by 
default because their users mostly use JACK just as a consumer desktop sound 
server. And I assume this applies to José as well.

Whereas JACK clients intended for musicians typically don't, because their 
common use case is to pipe audio through several music apps in their personal, 
and very custom way.

Then there are also a bunch of JACK clients with built-in support for some of 
the available session management standards. In this scenario you have another 
app, a session manager, which not only takes care about connections, but also 
actually starts all individual JACK client apps with their respective previous 
internal configurations.

Best regards,
Christian Schoenebeck