###### (This is the documentation for SDL3, which is the current stable version. [SDL2](https://wiki.libsdl.org/SDL2/) was the previous version!) # SDL_SetMemoryFunctions Replace SDL's memory allocation functions with a custom set. ## Header File Defined in [](https://github.com/libsdl-org/SDL/blob/main/include/SDL3/SDL_stdinc.h) ## Syntax ```c bool SDL_SetMemoryFunctions(SDL_malloc_func malloc_func, SDL_calloc_func calloc_func, SDL_realloc_func realloc_func, SDL_free_func free_func); ``` ## Function Parameters | | | | | ------------------------------------ | ---------------- | ------------------------ | | [SDL_malloc_func](SDL_malloc_func) | **malloc_func** | custom malloc function. | | [SDL_calloc_func](SDL_calloc_func) | **calloc_func** | custom calloc function. | | [SDL_realloc_func](SDL_realloc_func) | **realloc_func** | custom realloc function. | | [SDL_free_func](SDL_free_func) | **free_func** | custom free function. | ## Return Value (bool) Returns true on success or false on failure; call [SDL_GetError](SDL_GetError)() for more information. ## Remarks It is not safe to call this function once any allocations have been made, as future calls to [SDL_free](SDL_free) will use the new allocator, even if they came from an [SDL_malloc](SDL_malloc) made with the old one! If used, usually this needs to be the first call made into the SDL library, if not the very first thing done at program startup time. ## Thread Safety It is safe to call this function from any thread, but one should not replace the memory functions once any allocations are made! ## Version This function is available since SDL 3.1.3. ## See Also - [SDL_GetMemoryFunctions](SDL_GetMemoryFunctions) - [SDL_GetOriginalMemoryFunctions](SDL_GetOriginalMemoryFunctions) ---- [CategoryAPI](CategoryAPI), [CategoryAPIFunction](CategoryAPIFunction), [CategoryStdinc](CategoryStdinc)