###### (This is the documentation for SDL3, which is the current stable version. [SDL2](https://wiki.libsdl.org/SDL2/) was the previous version!) # SDL_GetAsyncIOSize Use this function to get the size of the data stream in an [SDL_AsyncIO](SDL_AsyncIO). ## Header File Defined in [](https://github.com/libsdl-org/SDL/blob/main/include/SDL3/SDL_asyncio.h) ## Syntax ```c Sint64 SDL_GetAsyncIOSize(SDL_AsyncIO *asyncio); ``` ## Function Parameters | | | | | ---------------------------- | ----------- | ----------------------------------------------------------------------- | | [SDL_AsyncIO](SDL_AsyncIO) * | **asyncio** | the [SDL_AsyncIO](SDL_AsyncIO) to get the size of the data stream from. | ## Return Value ([Sint64](Sint64)) Returns the size of the data stream in the [SDL_IOStream](SDL_IOStream) on success or a negative error code on failure; call [SDL_GetError](SDL_GetError)() for more information. ## Remarks This call is _not_ asynchronous; it assumes that obtaining this info is a non-blocking operation in most reasonable cases. ## Thread Safety It is safe to call this function from any thread. ## Version This function is available since SDL 3.2.0. ---- [CategoryAPI](CategoryAPI), [CategoryAPIFunction](CategoryAPIFunction), [CategoryAsyncIO](CategoryAsyncIO)