livekit::LocalDataTrack Class Reference

Represents a locally published data track. More...

#include <local_data_track.h>

Public Member Functions
	LocalDataTrack (const LocalDataTrack &)=delete
LocalDataTrack &	operator= (const LocalDataTrack &)=delete
const DataTrackInfo &	info () const noexcept
	Metadata about this data track.
Result< void, LocalDataTrackTryPushError >	tryPush (const DataTrackFrame &frame)
	Try to push a frame to all subscribers of this track.
Result< void, LocalDataTrackTryPushError >	tryPush (std::vector< std::uint8_t > &&payload, std::optional< std::uint64_t > user_timestamp=std::nullopt)
	Try to push a frame to all subscribers of this track.
Result< void, LocalDataTrackTryPushError >	tryPush (const std::uint8_t *data, std::size_t size, std::optional< std::uint64_t > user_timestamp=std::nullopt)
	Try to push a frame from a borrowed byte buffer.
bool	isPublished () const
	Whether the track is still published in the room.
void	unpublishDataTrack ()
	Unpublish this data track from the room.

Friends
class	LocalParticipant

Detailed Description

Represents a locally published data track.

Unlike audio/video tracks, data tracks do not extend the Track base class. They use a separate publish/unpublish lifecycle and carry arbitrary binary frames instead of media.

Created via LocalParticipant::publishDataTrack().

Typical usage:

auto lp = room->localParticipant().lock(); if (!lp) return; // room not connected or already torn down auto result = lp->publishDataTrack("sensor-data"); if (result) { auto dt = result.value(); DataTrackFrame frame; frame.payload = {0x01, 0x02, 0x03}; (void)dt->tryPush(frame); dt->unpublishDataTrack(); }

Member Function Documentation

tryPush() [1/3]

Result< void, LocalDataTrackTryPushError > livekit::LocalDataTrack::tryPush

(

const DataTrackFrame &

frame

)

Try to push a frame to all subscribers of this track.

An empty payload succeeds without sending a frame to subscribers.

Parameters

frame

The frame to push.

Returns

Success on delivery acceptance, or a typed error describing why the frame could not be queued.

tryPush() [2/3]

Result< void, LocalDataTrackTryPushError > livekit::LocalDataTrack::tryPush	(	const std::uint8_t *	data,
		std::size_t	size,
		std::optional< std::uint64_t >	user_timestamp = std::nullopt
	)

Try to push a frame from a borrowed byte buffer.

Copies size bytes from data into an FFI request before returning; the SDK does not retain the buffer. An empty payload succeeds without sending a frame to subscribers.

Note

This avoids an intermediate copy when the caller already owns a byte buffer, but it is not a zero-copy send.

Parameters

data	Pointer to size payload bytes. Must be non-null when size is non-zero.
size	Number of bytes at data. A value of zero is a successful no-op.
user_timestamp	Optional application-defined timestamp. The unit is caller-defined.

Returns

Success on delivery acceptance, or a typed error describing why the frame could not be queued.

tryPush() [3/3]

Result< void, LocalDataTrackTryPushError > livekit::LocalDataTrack::tryPush	(	std::vector< std::uint8_t > &&	payload,
		std::optional< std::uint64_t >	user_timestamp = std::nullopt
	)

Try to push a frame to all subscribers of this track.

An empty payload succeeds without sending a frame to subscribers.

Parameters

payload	The payload to push.
user_timestamp	Optional application-defined timestamp. The unit is caller-defined.

Returns

Success on delivery acceptance, or a typed error describing why the frame could not be queued.

unpublishDataTrack()

void livekit::LocalDataTrack::unpublishDataTrack

(

)

Unpublish this data track from the room.

After this call, tryPush() fails and the track cannot be re-published.

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The documentation for this class was generated from the following file:

• include/livekit/local_data_track.h