snd_pcm_get_filter()

Retrieves the PCM filters that your application is subscribed to.

Synopsis:

#include <sys/asoundlib.h>

int snd_pcm_get_filter( (snd_pcm_t *pcm,
                         int channel,
                         snd_pcm_filter_t * filter);

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().
channel
The channel for the PCM handle. SND_PCM_CHANNEL_CAPTURE or SND_PCM_CHANNEL_PLAYBACK.
filter
A pointer to a snd_pcm_event_t structure that snd_pcm_get_filter() fills in with the mask.

Library:

libasound.so

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

Description:

The snd_pcm_get_filter() function fills the snd_pcm_filter_t structure with a mask of all PCM events for the channel that the handle was opened on.

You can arrange to have your application receive notification when an event occurs by calling select() on the channel, You can use snd_pcm_channel_read_event() to read the event's data.

Returns:

EOK on success, a negative errno upon failure. The errno values are available in the errno.h file.

Errors:

-EINVAL
Invalid pcm or filter is NULL.

Classification:

QNX Neutrino

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