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ado_mixer_element_io()

Create an input/output element

Synopsis:

#include <audio_driver.h>

ado_mixer_delement_t *ado_mixer_element_io
  ( ado_mixer_t *mixer,
    char *name,
    int32_t type,
    uint32_t attrib,
    uint32_t number_of_voices,
    snd_mixer_voice_t *voices );

Arguments:

mixer

A pointer to the ado_mixer_t structure that specifies the mixer to create the element in. This structure was created by ado_mixer_create().

name

The name of the element. Elements are referred to by name, so be careful; for some standard names, see <asound.h>.

type

The type of element; one of:

• SND_MIXER_ETYPE_INPUT
• SND_MIXER_ETYPE_OUTPUT

attrib

Currently not used; set it to 0.

number_of_voices

The number of voices passing through the element.

voices

An array of snd_mixer_voice_t structures (see below). Each entry describes one of the voices.

Description:

The ado_mixer_element_io() convenience function automates the creation of an input/output element. An input/output element is usually a physical connector on the sound card.

The snd_mixer_voice_t structure is defined as:

typedef struct
{
    uint16_t  voice:15, vindex:1;
    uint8_t   reserved[124];
} snd_mixer_voice_t;

The members include:

voice

One of:

• SND_MIXER_VOICE_UNUSED
• SND_MIXER_VOICE_MONO
• SND_MIXER_VOICE_LEFT
• SND_MIXER_VOICE_RIGHT
• SND_MIXER_VOICE_CENTER
• SND_MIXER_VOICE_REAR_LEFT
• SND_MIXER_VOICE_REAR_RIGHT
• SND_MIXER_VOICE_WOOFER

vindex

Not used; set this to 0.

Returns:

A pointer to the newly allocated input/output element.

Classification:

QNX Neutrino