Re: [LAU] Jack-enabled CLI Player - Linux-audio-user

3 Aug 2009

...

 On Tuesday 04 August 2009 02:19:33 you wrote:

   On Sun,
2009-08-02 at 16:45 +0300, David Baron wrote:

  What might be a jack-enabled equivalent of:

 /usr/bin/ogg123 -d alsa<1>    (<1>   is and ogg file, obviously)

 Preferrable would be something that will play through jack if the daemon
 be running, alsa not (mplayer can work this way but this is a bit heavy
 for a short file play, i.e., a signal from a program).
            mplayer fits the bill perfectly imho and I'm not convinced that
it's
 that heavy - it actually uses very little memory when just playing a
 sound file (mp3, ogg, wave).
          Does mplayer auto sense if jack is being used and fall back to
 pulse/gstreamer/esd/alsa/oss if not? Maybe David just needs a small
 script that willl check the existance of a running jack and trigger the
 correct commandline.
        Done in mplayer with option -ao jack,alsa (pulse can be in this list as
well)!

That's very handy to know.

...
   Does anyone
have an example of a bash command to check if jack is running?

 ex. (untested)

 !# /bin/bash

 if(jack_connect 2>&1 | grep "server not running")

       alsaplayer -i text file.ogg

 else

       alsaplayer -i text -o jack file.ogg

  If you want a program to have "signal
sounds" an external sound player
 is bulky regardless of the player used. Jack itself also sounds a bit
 overkill. This sounds like the use-case for system sounds, esd, pulse,
 etc.
          I agree. Do you want this feature to work so that you can hear the phone
 calls when jack is running or do you have a more specific need for
 piping the audio through jack?
        I am using the computer, possibly for listening or audio using jack or not.
 The applet needs to work regardless.

I have a hunch that this will become a very common scenario so I might 
whip up a quick toot for this problem as an example for future 
reference... Would you be interested in added a section on your experience?

Just a few lines or a paragraph about what you needed to do and the 
solution would be very useful.

...
   IIUC the
latest version of pulse will use jack if it is running and
 reconfigure itself to use alsa directly when it is not running. This is
 the point of the dbus code.

 However I'm not 100% certain that Kjetils suggested method is the
 correct way to achieve this. I was under the impression that the latest
 version didn't need to be configured at all. The dbus code in jack2
 would take care of the call to reconfigure the i/o sinks. I think
 Kjetils suggestion means that jack has to be always on before pa is
 started.
        It would seem that configuration needs jack running to pulse will fail to
 start.