snd_pcm_query_channel

Get the current channel mapping for a PCM stream

Synopsis:

#include <sys/asoundlib.h>

int snd_pcm_query_channel_map( snd_pcm_t *pcm,
                               snd_pcm_chmap_t *chmap );

Arguments:

pcm: The handle for the PCM device, which you must have opened by calling snd_pcm_open_name(), snd_pcm_open(), or snd_pcm_open_preferred().
chmap: A pointer to a snd_pcm_chmap_t structure where the function can store the mapping. You must allocate this structure before calling this function.

Library:

libasound.so

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

Description:

(QNX Software Development Platform 6.6 io-audio patch [patch ID 4510] or later) The snd_pcm_query_channel_map() function gets the current channel mapping for a PCM stream and stores it in the given snd_pcm_chap_t structure.

Returns:

0 on success, or a negative errno value if an error occurred.

Errors:

-EINVAL: The value of pcm or chmap is NULL.
-ENOMEM: Not enough memory was available.
-

Classification:

QNX Neutrino

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	Yes
Thread	Read the Caveats

Caveats:

This function isn't thread-safe if pcm (snd_pcm_t) is used across multiple threads.