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snd_pcm_plugin_info()

Get information about a PCM channel's capabilities (plugin-aware)

Synopsis:

#include <sys/asoundlib.h>

int snd_pcm_plugin_info(
       snd_pcm_t *handle, 
       snd_pcm_channel_info_t *info );

Arguments:

handle
The handle for the PCM device, which you must have opened by calling snd_pcm_open() or snd_pcm_open_preferred().
info
A pointer to a snd_pcm_channel_info_t structure that snd_pcm_plugin_info() fills in with information about the PCM channel.

Before calling this function, set the info structure's channel member to specify the direction. This function sets all the other members.

Library:

libasound.so

Description:

The snd_pcm_plugin_info() function fills the info structure with data about the PCM channel selected by handle.


Note: This function and the nonplugin version, snd_pcm_channel_info(), get a dynamic "snapshot" of the system's current capabilities, which can shrink and grow as subchannels are allocated and freed. They're similar to snd_ctl_pcm_channel_info(), which gets information about the complete capabilities of the system.

Returns:

Zero on success, or a negative error code (errno is set).

Errors:

-EINVAL
Invalid handle.

Examples:

See the wave.c example in the appendix.

Classification:

QNX Neutrino

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

Caveats:

This function is the plugin-aware version of snd_pcm_channel_info(). It functions exactly the same way. However, make sure that you don't mix and match plugin- and nonplugin-aware functions in your application, or you may get undefined behavior and misleading results.

See also:

snd_pcm_channel_info(), snd_pcm_channel_info_t