snd_mixer_filter_t

Information about a mixer's filters

Synopsis:

typedef struct snd_mixer_filter
{
    uint32_t    enable;             /* bitfield of 1 << SND_MIXER_READ_* */
    uint8_t     reserved[124];      /* must be filled with zero */
}       snd_mixer_filter_t;

Description:

The snd_mixer_filter_t structure describes the filters for a mixer. You can call snd_mixer_set_filter() to specify the events you want to track, and snd_mixer_get_filter() to determine which you're tracking.

Currently, the only member of this structure is enable, which is a mask of the mixer events. The bits in the mask include:

SND_MIXER_READ_REBUILD

The mixer has been rebuilt.

SND_MIXER_READ_ELEMENT_VALUE

An element's value has changed.

SND_MIXER_READ_ELEMENT_CHANGE

An element has changed in some way other than its value.

SND_MIXER_READ_ELEMENT_ADD

An element was added to the mixer.

SND_MIXER_READ_ELEMENT_REMOVE

An element was removed from the mixer.

SND_MIXER_READ_ELEMENT_ROUTE

A route was added or changed.

SND_MIXER_READ_GROUP_VALUE

A group's value has changed.

SND_MIXER_READ_GROUP_CHANGE

A group has changed in some way other than its value.

SND_MIXER_READ_GROUP_ADD

A group was added to the mixer.

SND_MIXER_READ_GROUP_REMOVE

A group was removed from the mixer.

Classification:

QNX Neutrino

See also:

snd_mixer_get_filter(), snd_mixer_set_filter()