[LAU] make a VU meter listen to jack output ports

[Peter P.]

* Peter P. <peterparker at fastmail.com> [2015-06-14 13:22]:
[...]
> > Strangely this does not work when I start it from fluxbox' menu, ie.
> > without a visible (x)terminal. The application (and hence the
> > meterbridge) close immediately. Do you have an idea why this could
> > happen?
> 
> Sorry, I posted before doing my homework
> The --disable-console option helped here.

But I am afraid the the meters still don't come up every time.
The --no-stdin does not help as well, but has other unpleasant results.
It seems that jack_capture needs to have a console it can output things
to. 
>From ~/.fluxbox/menu I am starting it as 

jack_capture -dc --meterbridge --meterbridge-type dpm --timemachine --port system:playback_1 --port system:playback_2 /dev/null

and in .xsession-errors I get

>>> Warning. Could not set higher priority for a SCHED_FIFO process
>>> using setpriority().
>>> Waiting to start recording of "/dev/null"
>>> Press <Ctrl-C> to stop recording and quit.
>>> Recording. Press <Return> to stop.
Finished.
>>> Error: exec returned.
>>> jack_capture encountered 1 jack x-runs.

Furthermore, automatically reconnecting to jack applications which play
back audio, does only happen if jack_capture/meterbridge have been
started when that application (mplayer in my case) was already playing
back.

Thank you for any hints,
P