Provided by: libsdl3-doc_3.2.8+ds-1_all 

NAME
SDL_GetAsyncIOSize - Use this function to get the size of the data stream in an SDL_AsyncIO .
HEADER FILE
Defined in SDL3/SDL_asyncio.h
SYNOPSIS
#include "SDL3/SDL.h" Sint64 SDL_GetAsyncIOSize(SDL_AsyncIO *asyncio);
DESCRIPTION
This call is _not_ asynchronous; it assumes that obtaining this info is a non-blocking operation in most reasonable cases.
FUNCTION PARAMETERS
asyncio the SDL_AsyncIO to get the size of the data stream from.
RETURN VALUE
( Sint64 ) Returns the size of the data stream in the SDL_IOStream on success or a negative error code on failure; call SDL_GetError () for more information.
THREAD SAFETY
It is safe to call this function from any thread.
AVAILABILITY
This function is available since SDL 3.2.0. Simple Directmedia Layer SDL 3.2.8 SDL_GetAsyncIOSize(3)