Re: [Alsa-devel] Re: 2.6.10-mm1: ALSA ac97 compile error with CONFIG_PM=n

[Lee Revell <rlrevell@joe-job.com>]

On Wed, 2005-01-05 at 14:56 +0000, Alan Cox wrote:
> On Mer, 2005-01-05 at 14:21, Mark_H_Johnson@raytheon.com wrote:
> > > The default blocking behavior of OSS devices was changed recently.
> > > When the device is in use, open returns -EBUSY immediately in the
> > > latest version while it was blocked until released in the former
> > > version.
> > I suppose there was a "good reason" for changing the user level
> > interface in this way. Could you [or someone else] explain that and
> > if you would consider changing it back (to stop breaking old applications)?
> > Otherwise - is there some way (other than running lsmod and grep) to find
> > out if the interface is busy and which application is using it?
> 
> OSS itself changed behaviour over time (2.2 to 2.4) ALSA has merely
> caught up with the newer OSS behaviour and the new behaviour is correct.
> 
> If you want to find out if the interface is busy open it. If you want to
> do it portably open it with O_NDELAY.
> 

And if you want to find out who is using it then try fuser /dev/dsp,
fuser /dev/snd/*, or lsof.

Lee