[linux-audio-user] alsa setup debug (was: jackd -d alsa -d hw:0 -p512 / problem to start)

[Benjamin Flaming]

On Thu, 30 Oct 2003 19:19:31 +0100
Tim Orford <tim at orford.org> wrote:

> > > pls post the first few lines of jack output.
> > 
> > # jackd -d alsa -d hw:0 -p512 |head -n 6
> > JACK compiled with System V SHM support
> > loading driver ..
> > open
> > starting engine
> > 
> > **** alsa_pcm: xrun of at least 0.060 msecs
> 
> unfortunately, head is not showing some output from jack.
> 
> you are missing this line:
> creating alsa driver ... hw:0|hw:0|4096|2|48000|nomon|swmeter|rt
> 
> this is useful cos it shows how jack is actually running.

This particular line is sent to stderr, instead of stdout (which is what head would be reading from).  I'd suggest the following:

jackd -v -d alsa -d hw:0 -p 512 1> jackstdout 2> jackerrout

Let it run for half a second, and then kill it with Ctrl-c.  Both files (jackstdout and jackerrout) should contain more detailed information about what's going on.

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