Function SDL_OpenAudioDeviceStream 

pub unsafe extern "C" fn SDL_OpenAudioDeviceStream(
    devid: SDL_AudioDeviceID,
    spec: *const SDL_AudioSpec,
    callback: SDL_AudioStreamCallback,
    userdata: *mut c_void,
) -> *mut SDL_AudioStream

Convenience function for straightforward audio init for the common case.

If all your app intends to do is provide a single source of PCM audio, this function allows you to do all your audio setup in a single call.

This is also intended to be a clean means to migrate apps from SDL2.

This function will open an audio device, create a stream and bind it. Unlike other methods of setup, the audio device will be closed when this stream is destroyed, so the app can treat the returned SDL_AudioStream as the only object needed to manage audio playback.

Also unlike other functions, the audio device begins paused. This is to map more closely to SDL2-style behavior, since there is no extra step here to bind a stream to begin audio flowing. The audio device should be resumed with SDL_ResumeAudioStreamDevice().

This function works with both playback and recording devices.

The spec parameter represents the app’s side of the audio stream. That is, for recording audio, this will be the output format, and for playing audio, this will be the input format. If spec is NULL, the system will choose the format, and the app can use SDL_GetAudioStreamFormat() to obtain this information later.

If you don’t care about opening a specific audio device, you can (and probably should), use SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK for playback and SDL_AUDIO_DEVICE_DEFAULT_RECORDING for recording.

One can optionally provide a callback function; if NULL, the app is expected to queue audio data for playback (or unqueue audio data if capturing). Otherwise, the callback will begin to fire once the device is unpaused.

Destroying the returned stream with SDL_DestroyAudioStream will also close the audio device associated with this stream.

Parameters

• devid: an audio device to open, or SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK or SDL_AUDIO_DEVICE_DEFAULT_RECORDING.
• spec: the audio stream’s data format. Can be NULL.
• callback: a callback where the app will provide new data for playback, or receive new data for recording. Can be NULL, in which case the app will need to call SDL_PutAudioStreamData or SDL_GetAudioStreamData as necessary.
• userdata: app-controlled pointer passed to callback. Can be NULL. Ignored if callback is NULL.

Return value

Returns an audio stream on success, ready to use, or NULL on failure; call SDL_GetError() for more information. When done with this stream, call SDL_DestroyAudioStream to free resources and close the device.

Thread safety

It is safe to call this function from any thread.

Availability

This function is available since SDL 3.2.0.

See also

• SDL_GetAudioStreamDevice
• SDL_ResumeAudioStreamDevice