Service queries and device creation. More...

Functions
XtServiceCaps	XtServiceGetCapabilities (XtService const *s)
	Get service capabilities. More...

XtError	XtServiceOpenDevice (XtService const s, char const id, XtDevice **device)
	Open an audio device. More...

XtError	XtServiceOpenDeviceList (XtService const s, XtEnumFlags flags, XtDeviceList *list)
	Enumerate available devices. More...

XtError	XtServiceGetDefaultDeviceId (XtService const s, XtBool output, XtBool valid, char buffer, int32_t size)
	Get default device id. More...

XtError	XtServiceAggregateStream (XtService const s, XtAggregateStreamParams const params, void user, XtStream *stream)
	Combines multiple audio devices into a single stream. More...

Detailed Description

Service queries and device creation.

Contains functions to query service capabilities and open devices.

Function Documentation

XtError XtServiceAggregateStream	(	XtService const *	s,
		XtAggregateStreamParams const *	params,
		void *	user,
		XtStream **	stream
	)

Combines multiple audio devices into a single stream.

Returns: 0 on success, a nonzero error code otherwise.

Parameters

s	the audio service.
params	the stream parameters.
user	user data passed to the stream callbacks (may be NULL).
stream	on success, receives a pointer to the opened audio stream. On error, *stream will be NULL.

Each underlying stream is opened using the combination of the shared mix format and the device-specific channel specification as the audio format.

Aggregate streams use an intermediate buffer to keep underlying streams in sync. The total latency overhead of the aggregate stream is bounded by the largest buffer size of any of the underlying streams times a constant factor.

Use XtDeviceGetBufferSize to query supported buffer sizes. The resulting stream must be closed using XtStreamDestroy.

When the requested interleaving mode is not supported by any device it will be emulated.

The service must support stream aggregation (XtServiceCapsAggregation).

This function may only be called from the main thread.

See also: XtStreamDestroy; XtDeviceOpenStream; XtDeviceSupportsFormat; XtDeviceSupportsAccess; XtServiceCapsAggregation

XtServiceCaps XtServiceGetCapabilities ( XtService const * s )

Get service capabilities.

Returns: the capabilities for the given service.

Parameters

s	the audio service.

This function may be called from any thread.

See also: XtFormat; XtBuffer; XtStreamGetLatency; XtServiceAggregateStream; XtDeviceShowControlPanel; XtOnXRun

XtError XtServiceGetDefaultDeviceId	(	XtService const *	s,
		XtBool	output,
		XtBool *	valid,
		char *	buffer,
		int32_t *	size
	)

Get default device id.

Returns: 0 on success, a nonzero error code otherwise.

Parameters

s	the audio service.
output	XtTrue for default output device, XtFalse for default input device
valid	on success, *valid will be true if a default device is present
buffer	the string buffer to receive the device id. If NULL, *size receives the required buffer size.
size	the size of the buffer.

It is NOT an error when no default device is present.

See also: XtDeviceListGetId; XtServiceOpenDevice

XtError XtServiceOpenDevice	(	XtService const *	s,
		char const *	id,
		XtDevice **	device
	)

Open an audio device.

Returns: 0 on success, a nonzero error code otherwise.

Parameters

s	the audio service.
id	the device id.
device	on success, receives a pointer to the opened device. On error, *device is set to NULL.

Use XtDeviceDestroy to clean up the device.

This function may only be called from the main thread.

See also: XtDeviceDestroy; XtDeviceListGetId; XtServiceGetDefaultDeviceId

XtError XtServiceOpenDeviceList	(	XtService const *	s,
		XtEnumFlags	flags,
		XtDeviceList **	list
	)

Enumerate available devices.

Returns: 0 on success, a nonzero error code otherwise.

Parameters

s	the audio service.
flags	specifies whether to enumerate input, output or all devices.
list	on success, receives a pointer to the opened device list. On error, *list is set to NULL.

Use XtDeviceListDestroy to clean up the device list.

This function may only be called from the main thread.

See also: XtDeviceListDestroy; XtDeviceListGetId; XtDeviceListGetCount; XtServiceGetDefaultDeviceId; XtServiceOpenDevice

Functions

Detailed Description

Function Documentation