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
Use the -l asound option with
qcc
to link against this library.
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 |