###### (This is the legacy documentation for stable SDL2, the current stable version; [SDL3](https://wiki.libsdl.org/SDL3/) is the current development version.) # SDL_Init Initialize the SDL library. ## Syntax ```c int SDL_Init(Uint32 flags); ``` ## Function Parameters | | | | ------------- | ------------------------------ | | **flags** | subsystem initialization flags | ## Return Value Returns 0 on success or a negative error code on failure; call [SDL_GetError](SDL_GetError)() for more information. ## Remarks [SDL_Init](SDL_Init)() simply forwards to calling [SDL_InitSubSystem](SDL_InitSubSystem)(). Therefore, the two may be used interchangeably. Though for readability of your code [SDL_InitSubSystem](SDL_InitSubSystem)() might be preferred. The file I/O (for example: [SDL_RWFromFile](SDL_RWFromFile)) and threading ([SDL_CreateThread](SDL_CreateThread)) subsystems are initialized by default. Message boxes ([SDL_ShowSimpleMessageBox](SDL_ShowSimpleMessageBox)) also attempt to work without initializing the video subsystem, in hopes of being useful in showing an error dialog when [SDL_Init](SDL_Init) fails. You must specifically initialize other subsystems if you use them in your application. Logging (such as [SDL_Log](SDL_Log)) works without initialization, too. `flags` may be any of the following OR'd together: - [`SDL_INIT_TIMER`](SDL_INIT_TIMER): timer subsystem - [`SDL_INIT_AUDIO`](SDL_INIT_AUDIO): audio subsystem - [`SDL_INIT_VIDEO`](SDL_INIT_VIDEO): video subsystem; automatically initializes the events subsystem - [`SDL_INIT_JOYSTICK`](SDL_INIT_JOYSTICK): joystick subsystem; automatically initializes the events subsystem - [`SDL_INIT_HAPTIC`](SDL_INIT_HAPTIC): haptic (force feedback) subsystem - [`SDL_INIT_GAMECONTROLLER`](SDL_INIT_GAMECONTROLLER): controller subsystem; automatically initializes the joystick subsystem - [`SDL_INIT_EVENTS`](SDL_INIT_EVENTS): events subsystem - [`SDL_INIT_EVERYTHING`](SDL_INIT_EVERYTHING): all of the above subsystems - [`SDL_INIT_NOPARACHUTE`](SDL_INIT_NOPARACHUTE): compatibility; this flag is ignored Subsystem initialization is ref-counted, you must call [SDL_QuitSubSystem](SDL_QuitSubSystem)() for each [SDL_InitSubSystem](SDL_InitSubSystem)() to correctly shutdown a subsystem manually (or call [SDL_Quit](SDL_Quit)() to force shutdown). If a subsystem is already loaded then this call will increase the ref-count and return. ## Version This function is available since SDL 2.0.0. ## Related Functions * [SDL_InitSubSystem](SDL_InitSubSystem) * [SDL_Quit](SDL_Quit) * [SDL_SetMainReady](SDL_SetMainReady) * [SDL_WasInit](SDL_WasInit) ---- [CategoryAPI](CategoryAPI), [CategoryInit](CategoryInit)