Unable to open plughw:0,0 from user program.

Unable to open plughw:0,0 from user program.

[stan]

Hi,

I am unable to use plughw:0,0 as a device string while calling
err = snd_pcm_open (&alsa_dev, hw_from_default, SND_PCM_STREAM_PLAYBACK, 0);

The same call works with hw_from_default == 'default', but fails when it 
is 'plughw:0,0'.
The error is
cannot open audio device "plughw:0,0" (Device or resource busy)

I am using the latest snapshot of alsa-lib, alsa-lib20070821.  I tried 
debugging but I cannot trace through the macros.  As near as I can tell 
there have been no changes to alsa.conf, and this worked just fine 
before the latest upgrade alsa package alsa-lib.1.0.14-3

Is this a deliberate change in alsa that is known about, and is there a 
way to still get the functionality?

Thanks.

Re: Unable to open plughw:0,0 from user program.

[stan]

stan wrote:
> Hi,
>
> I am unable to use plughw:0,0 as a device string while calling
> err = snd_pcm_open (&alsa_dev, hw_from_default, 
> SND_PCM_STREAM_PLAYBACK, 0);
>
> The same call works with hw_from_default == 'default', but fails when 
> it is 'plughw:0,0'.
> The error is
> cannot open audio device "plughw:0,0" (Device or resource busy)
>
> I am using the latest snapshot of alsa-lib, alsa-lib20070821.  I tried 
> debugging but I cannot trace through the macros.  As near as I can 
> tell there have been no changes to alsa.conf, and this worked just 
> fine before the latest upgrade alsa package alsa-lib.1.0.14-3
>
> Is this a deliberate change in alsa that is known about, and is there 
> a way to still get the functionality?
>
> Thanks.
>
Forgot to mention that this is on Fedora Rawhide with a 2.6.23 kernel.  
Want to see if it is normal in the latest versions of alsa before I 
pursue it through bugzilla with Fedora.

Re: Unable to open plughw:0,0 from user program.

[Takashi Iwai]

At Thu, 23 Aug 2007 11:44:56 -0700,
stan wrote:
> 
> Hi,
> 
> I am unable to use plughw:0,0 as a device string while calling
> err = snd_pcm_open (&alsa_dev, hw_from_default, SND_PCM_STREAM_PLAYBACK, 0);
> 
> The same call works with hw_from_default == 'default', but fails when it 
> is 'plughw:0,0'.
> The error is
> cannot open audio device "plughw:0,0" (Device or resource busy)

Maybe the devce is really in use?
Try "fuser /dev/snd/*"

> I am using the latest snapshot of alsa-lib, alsa-lib20070821.  I tried 
> debugging but I cannot trace through the macros.  As near as I can tell 
> there have been no changes to alsa.conf, and this worked just fine 
> before the latest upgrade alsa package alsa-lib.1.0.14-3
> 
> Is this a deliberate change in alsa that is known about, and is there a 
> way to still get the functionality?

The old library binary might still remain.  Some distros install
libasound in /lib (or /lib64), instead of /usr/lib (or /usr/lib64).


Takashi

Re: Unable to open plughw:0,0 from user program.

[stan]

Takashi Iwai wrote:
> At Thu, 23 Aug 2007 11:44:56 -0700,
> stan wrote:
>   
>> Hi,
>>
>> I am unable to use plughw:0,0 as a device string while calling
>> err = snd_pcm_open (&alsa_dev, hw_from_default, SND_PCM_STREAM_PLAYBACK, 0);
>>
>> The same call works with hw_from_default == 'default', but fails when it 
>> is 'plughw:0,0'.
>> The error is
>> cannot open audio device "plughw:0,0" (Device or resource busy)
>>     
>
> Maybe the devce is really in use?
> Try "fuser /dev/snd/*"
>
>   
I don't think so.  Here is the output of fuser /dev/snd/*
/dev/snd/pcmC0D0p:    3069m
/dev/snd/timer:       3069

And I open default just before this in order to get its info so I can 
build the plughw.
Default device number (0)
Default subdevice number (0)
Default stream number (0)
Default card number (-1)
Default id (dmix:0,FORMAT=S32_LE)
Default name (dmix:0,FORMAT=S32_LE)
Default subname (dmix:0,FORMAT=S32_LE)
Default dev_class (0)
Default dev_subclass (0)
Default subdevices_count (1)
Default subdevices_avail (0)
Plughw  plughw:0,0  numchars 10
cannot open audio device "plughw:0,0" (Device or resource busy)

>> I am using the latest snapshot of alsa-lib, alsa-lib20070821.  I tried 
>> debugging but I cannot trace through the macros.  As near as I can tell 
>> there have been no changes to alsa.conf, and this worked just fine 
>> before the latest upgrade alsa package alsa-lib.1.0.14-3
>>
>> Is this a deliberate change in alsa that is known about, and is there a 
>> way to still get the functionality?
>>     
>
> The old library binary might still remain.  Some distros install
> libasound in /lib (or /lib64), instead of /usr/lib (or /usr/lib64).
>
>   
I'm changing  the links to point to the new library, and adding an alsa 
file in /etc/ld.so.conf.d/ so that the cache points to my library.  When 
I run ldd on the binary it points to the library I've compiled.
 ldd discord
        linux-gate.so.1 =>  (0x00110000)
        libm.so.6 => /lib/libm.so.6 (0x00939000)
        libpthread.so.0 => /lib/libpthread.so.0 (0x0096b000)
*        libasound.so.2 => /usr/local/lib/alsa/libasound.so.2 (0x00111000)*
        libncurses.so.5 => /lib/libncurses.so.5 (0x06707000)
        libsndfile.so.1 => /usr/lib/libsndfile.so.1 (0x001f7000)
        libsamplerate.so.0 => /usr/lib/libsamplerate.so.0 (0x00257000)
        libc.so.6 => /lib/libc.so.6 (0x007e2000)
        /lib/ld-linux.so.2 (0x007c3000)
        libdl.so.2 => /lib/libdl.so.2 (0x00964000)
        libtinfo.so.5 => /lib/libtinfo.so.5 (0x066ed000)

> Takashi
>
>   
I can see it call snd_config_search_alias_hooks () in conf.c, but lose 
the debug in the macros, and it comes back from the macros with the 
negative error code.

Thanks for your help.

Re: Unable to open plughw:0,0 from user program.

[Lee Revell]

On 8/23/07, stan <stanl@cox.net> wrote:
> I don't think so.  Here is the output of fuser /dev/snd/*
> /dev/snd/pcmC0D0p:    3069m
> /dev/snd/timer:       3069

Looks like it's in use by process 3069?  What is that?

Lee

Re: Unable to open plughw:0,0 from user program.

[stan]

Lee Revell wrote:
> On 8/23/07, stan <stanl@cox.net> wrote:
>   
>> I don't think so.  Here is the output of fuser /dev/snd/*
>> /dev/snd/pcmC0D0p:    3069m
>> /dev/snd/timer:       3069
>>     
>
> Looks like it's in use by process 3069?  What is that?
>
> Lee
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel@alsa-project.org
> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
>
>   
That is esd, Esound daemon.

NAME
       esd - The Enlightened Sound Daemon

DESCRIPTION
       Starts up EsounD, which provides a sound mixing server.

USAGE
       esd [options]

         -d DEVICE     force esd to use sound device DEVICE
         -b            run server in 8 bit sound mode
         -r RATE       run server at sample rate of RATE
         -as SECS      free audio device after SECS of inactivity (-1 to 
disable)
         -unix         use unix domain sockets instead of tcp/ip
         -tcp          use tcp/ip sockets instead of unix domain
         -public       make tcp/ip access public (other than localhost)
         -promiscuous  start unlocked and owned (disable authenticaton) 
NOT RECOMMENDED
         -terminate    terminate esd daemon after last client exits
         -noterminate  do not terminate esd daemon after last client exits
         -nobeeps      disable startup beeps
         -beeps        enable startup beeps
         -trust        start esd even if use of /tmp/.esd can be insecure
         -port PORT    listen for connections at PORT (only for tcp/ip)
         -bind ADDRESS binds to ADDRESS (only for tcp/ip)

         -v --version  print version information

       Possible devices are:  /dev/dsp, /dev/dsp2, etc.

FILES /etc/esd.conf           daemon configuration file

And it must be my problem.  It must have been started by default because 
I didn't start it.  I'll see if I can configure it to share the sound 
card or disable it.

Thank you very much.

Re: Unable to open plughw:0,0 from user program.

[Lee Revell]

On 8/23/07, stan <stanl@cox.net> wrote:
> And it must be my problem.  It must have been started by default because
> I didn't start it.  I'll see if I can configure it to share the sound
> card or disable it.

I would disable it, as you have seen, sound server is not necessary to
share the soundcard anymore - alsa-lib/dmix handles it.

Lee

Re: Unable to open plughw:0,0 from user program.

[stan]

Lee Revell wrote:
> On 8/23/07, stan <stanl@cox.net> wrote:
>   
>> And it must be my problem.  It must have been started by default because
>> I didn't start it.  I'll see if I can configure it to share the sound
>> card or disable it.
>>     
>
> I would disable it, as you have seen, sound server is not necessary to
> share the soundcard anymore - alsa-lib/dmix handles it.
>
> Lee
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel@alsa-project.org
> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
>
>   
That makes sense, I'll get rid of it.