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snd_ctl_pcm_channel_info()

Get information about a PCM channel's capabilities from a control handle

Synopsis:

#include <sys/asoundlib.h>

int snd_ctl_pcm_channel_info(
       snd_ctl_t *handle, 
       int dev,
       int chn,
       int subdev,
       snd_pcm_channel_info_t *info );

Arguments:

handle
The handle for the control connection to the card. This must be a handle created by snd_ctl_open().
dev
The PCM device number.
chn
The channel direction; either SND_PCM_CHANNEL_CAPTURE or SND_PCM_CHANNEL_PLAYBACK.
subdev
The PCM subchannel.
info
A pointer to a snd_pcm_channel_info_t structure in which snd_ctl_pcm_channel_info() stores the information.

Library:

libasound.so

Description:

The snd_ctl_pcm_channel_info() function fills the info structure with data about the PCM subchannel subdev in the PCM channel chn on the sound card selected by handle.


Note: This function gets information about the complete capabilities of the system. It's similar to snd_pcm_channel_info() and snd_pcm_plugin_info(), but these functions get a dynamic “snapshot” of the system's current capabilities, which can shrink and grow as subchannels are allocated and freed.

Returns:

Zero on success, or a negative error code.

Errors:

-EINVAL
Invalid handle.

Classification:

QNX Neutrino

Safety:
Cancellation point No
Interrupt handler No
Signal handler Yes
Thread Yes

See also:

snd_ctl_open(), snd_pcm_channel_info(), snd_pcm_channel_info_t, snd_pcm_plugin_info()