[alsa-devel] alsa-lib, dmix, and snd_pcm_open_conf function
Hi,
I have a problem using dmix on my embedded system (manual installation of alsa-lib 1.0.15)
When I play a sound with aplay, it works well.
When I try -D dmix or -D plug:dmix parameter, it doesn't work.
The output is:
aplay: main:547: audio open error: Operation not permitted
I located my problem in alsa-lib, around line 2154 of alsa-lib/src/pcm/pcm.c:
err = snd_pcm_open_conf(pcmp, name, root, pcm_conf, stream, mode); (in snd_pcm_open_noupdate function)
err result is -1 when it's used with dmix...
I don't know how works alsa-lib. I suppose snd_pcm_open_conf has something related with configuration files... Since I have all default configuration files... Maybe I must tweak some to be able to use dmix...
Simon Tremblay <bidou <at> videotron.qc.ca> writes:
I located my problem in alsa-lib, around line 2154 of alsa-lib/src/pcm/pcm.c:
err = snd_pcm_open_conf(pcmp, name, root, pcm_conf, stream, mode); (in snd_pcm_open_noupdate function)
err result is -1 when it's used with dmix...
Note that I get 1 for snd_config_search_definition return value.
On Mon, 1 Sep 2008, Simon Tremblay wrote:
Hi,
I have a problem using dmix on my embedded system (manual installation of alsa-lib 1.0.15)
When I play a sound with aplay, it works well.
When I try -D dmix or -D plug:dmix parameter, it doesn't work.
The output is:
aplay: main:547: audio open error: Operation not permitted
strace will help you. I would look to ipc permissions (alsa.conf):
defaults.pcm.ipc_gid audio defaults.pcm.ipc_perm 0660
Jaroslav
----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.
Jaroslav Kysela a écrit :
On Mon, 1 Sep 2008, Simon Tremblay wrote:
Hi,
I have a problem using dmix on my embedded system (manual installation of alsa-lib 1.0.15)
When I play a sound with aplay, it works well.
When I try -D dmix or -D plug:dmix parameter, it doesn't work.
The output is:
aplay: main:547: audio open error: Operation not permitted
strace will help you. I would look to ipc permissions (alsa.conf):
defaults.pcm.ipc_gid audio defaults.pcm.ipc_perm 066
Thanks, but I just want to know where I manage that for IPC? I created an audio group and my /dev/snd/* files are in this group and have 0660 as permissions.
Simon
participants (2)
-
Jaroslav Kysela
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Simon Tremblay