[LAD] [Jack-Devel] A picture...of the global mess

Jack O'Quin jack.oquin at gmail.com
Wed May 20 21:43:33 UTC 2009

On Wed, May 20, 2009 at 2:38 PM, Fons Adriaensen <fons at kokkinizita.net> wrote:
> On Tue, May 19, 2009 at 04:23:30PM +0200, Stéphane Letz wrote:
>> A picture to try  summary what I understand about we would like :
>> -  "jackcontrol" is an *always" running deamon that defined an entry IPC
>> point.  jackcontrol get requests from control applications. "jackcontrol"
>> can start a seprated server called "jackserver (using a fork+exec) way.
>> "jackcontrol" is a *unique* place where setting are handled.
>> - "jackd" is a recoded  control application that parse it's command line,
>> and use the control IPC to speak to "jackcontrol" (then just quits).
>> jackcontrol then start the "jackserver" whith the appropriate paramaters.
> You don't need this jackd. If all the IPC is in libjack, an
> autostart request can be passed directly to jackcontrol without
> creating a transient process.
> 1. Client uses jack_client_open() with autostart.
> 2. Libjack doesn't find the server
> 3. Libjack sends 'start server' to jackcontrol
> 4. jackcontrol starts the server
> 5. jackcontrol notifies libjack
> 6. The jack_client_open() call proceeds.
> Between 3 and 5 the thread doing the original call
> (i.e. the client's thread) just waits within libjack
> for the ok/fail message from jackcontrol.

Don't forget a timeout in case the fork/exec fails and there is no message.

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