[LAD] qjackctl & server name

[drew Roberts]

On Sunday 06 June 2010 17:53:44 Rui Nuno Capela wrote:
> On 06/06/2010 10:16 PM, fons at kokkinizita.net wrote:
> > On Sun, Jun 06, 2010 at 10:12:45PM +0100, Rui Nuno Capela wrote:
> >> On 06/06/2010 09:43 PM, fons at kokkinizita.net wrote:
> >>> Qjackctl has the -n option to select a Jack server name,
> >>> and recent versions also allow multiple presets.
> >>>
> >>> What would it take to make the server name a element of
> >>> a preset rather than a command line option ?
> >>>
> >>> That would finally allow to run multiple jacks on the
> >>> same machine (something I've been doing quite a lot
> >>> recently) without having to start each qjackctl with
> >>> a different command line option (e.g. from a desktop
> >>> menu).
> >>>
> >>> And maybe the four start/stop scripts should also be
> >>> 'per preset'.
> >>>
> >>> While we're here: almost no apps support selecting a
> >>> specific Jack server. I've been adding this to some
> >>> of my own just because I needed it.
> >>> Using -n for this can be problematic if the toolset
> >>> used doesn't allow context-sensitive options: -n is
> >>> also used as a parameter for an ALSA interface, and
> >>> some apps support both Jack and ALSA.
> >>
> >> JACK_DEFAULT_SERVER environment variable might be your (only) friend
> >> here :)
> >
> > I know. Either that or for qjackctl, -n. But both require
> > the choice to be made when the app (in casu qjackctl) is
> > launched, while everything else, including the soundcard
> > to be used, can be selected later or as part of a preset.
> > Both JACK_DEFAULT_SERVER or -n also integrate badly with
> > desktop menus or icons used to start a qjackctl instance.
> >
> > If the soundcard used is part of a preset, the server
> > should be as well. Just give it a sensible default, so
> > 'almost all' users will never have to modify it.
>
> yep. i'm first to reckon qjackctl was not made/designed for the
> multi-jack-server scenario and the previously suggested hack are, yes,
> just a hack.
>
> but, as to let any of those client apps connect to the right jack server
> (-n), you probably need to lauch them in the right context, ah, unless i
> miss the point so badly, that means a precise JACK_DEFAULT_SERVER
> contextual (aka shell) setting anyhow
>
> :/

Hold on a second. Let me try walking through this.

We start qjackctl. Does it connect to a jack server at this point? If so, 
always or only if jack is currently running.

In cases where it might connect on startup, must it?

Let's say no jack is running and we start qjackctl.
Let's say it doesn't connect to jack at this point.
Could there not be a setup option to indicate what -n indicated now?

Let's say multiple jacks are running and we start qjackctl.
Is it possible to discover that multiple jacks are running?
If so, would it be possible to allow a choice from within the gui as to which 
one to connect to?

(I am asking these questions from a position of deep ignorance but having 
followed this discussion some and trying to help with any misunderstanding.)

all the best,

drew