[MPlayer-users] mplayer's jack name

Reimar Döffinger Reimar.Doeffinger at stud.uni-karlsruhe.de
Thu Aug 18 11:11:02 CEST 2005

On Thu, Aug 18, 2005 at 05:58:00PM +1000, etienne deleflie wrote:
> I just did a test, to see how other Jack enabled applications handle 
> multiple instances.
> PureData comes up as:
> pure_data_0
> pure_data_1
> pure_data_2
> Alsaplayer uses the PID .... bad example to set!!

bio2jack uses the PID, maybe that is the reason. Anyway, it actually is
a good idea to do it like that, e.g. if you want to set up a connection
for a program you just started - it's easy to find out which PID it got,
whereas the nameing of PureData is completely unpredictable.
Newer JACK libs provide a function to create a colission free name, but
I don't see much of an advantage in it.
I made a suboption that allows you specifying a name.
You can get the advantage of both by specifying -ao jack:name=test,jack.
It then first tries connecting with the name "test", and if that fails
with the default "MPlayer [<PID>]".

> and TimeMachine just uses "timemachine" and then the second instance 
> says "cant connect to Jack server".

The easy solution :-)

> So it seems there is not really a standard for how to handle this 
> situation.... I'd say the incrementor could be suggested as a standard 
> solution.

The very worst solution IMHO.

> >That could be done, but what if a stray/zombie MPlayer -ao jack is running 
> >and you start your chain of interconnected Jack-aware applications which 
> >include MPlayer?
> >
> I am not an Mplayer developer .... but as a developer, I believe that it 
> is not good programming practise to let an errorneous situation 
> determine behaviour for a non-erroneous siutuation.  ;-)

It is not good programming practise to ignore the errorneous situation

> Also, it would be more user friendly to not have to include an extra 
> command line argument to have the functionality of multiple instances of 
> Mplayer.

No, that certainly is not acceptable.

Reimar Döffinger

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