NAME

       SDL_SetAudioStreamGetCallback - Set a callback that runs when data is requested from an audio stream.

HEADER FILE

       Defined in SDL3/SDL_audio.h

SYNOPSIS

       #include "SDL3/SDL.h"

       bool SDL_SetAudioStreamGetCallback(SDL_AudioStream *stream, SDL_AudioStreamCallback callback, void *userdata);

DESCRIPTION

       This  callback is called _before_ data is obtained from the stream, giving the callback the chance to add
       more on-demand.

       The callback can (optionally) call

       SDL_PutAudioStreamData () to add more audio to the stream during this call; if needed, the  request  that
       triggered this callback will obtain the new data immediately.

       The  callback's  additional_amount  argument  is  roughly  how  many  bytes of _unconverted_ data (in the
       stream's input format) is needed by the caller, although this may overestimate a little for safety.  This
       takes into account how much is already in the stream and only asks for any extra necessary to resolve the
       request, which means the callback may be asked for zero bytes, and a different amount on each call.

       The  callback  is not required to supply exact amounts; it is allowed to supply too much or too little or
       none at all. The caller will get what's available, up to the amount they requested,  regardless  of  this
       callback's outcome.

       Clearing or flushing an audio stream does not call this callback.

       This  function obtains the stream's lock, which means any existing callback (get or put) in progress will
       finish running before setting the new callback.

       Setting a NULL function turns off the callback.

FUNCTION PARAMETERS

       stream the audio stream to set the new callback on.

       callback
              the new callback function to call when data is requested from the stream.

       userdata
              an opaque pointer provided to the callback for its own personal use.

RETURN VALUE

       Returns true on success or false on failure; call

       SDL_GetError () for more information. This only fails if stream is NULL.

THREAD SAFETY

       It is safe to call this function from any thread.

AVAILABILITY

       This function is available since SDL 3.2.0.

SEE ALSO

       •(3), SDL_SetAudioStreamPutCallback(3)

Simple Directmedia Layer                           SDL 3.2.10                   SDL_SetAudioStreamGetCallback(3)