SDL will always ensure that the passed nmemb and size are both greater
than 0.
\param nmemb the number of elements in the array.
\param size the size of each element of the array.
\returns a pointer to the allocated array, or NULL if allocation failed.
\threadsafety It should be safe to call this callback from any thread.
\since This datatype is available since SDL 3.2.0.
A callback used to implement SDL_calloc().
SDL will always ensure that the passed nmemb and size are both greater than 0.
\param nmemb the number of elements in the array. \param size the size of each element of the array. \returns a pointer to the allocated array, or NULL if allocation failed.
\threadsafety It should be safe to call this callback from any thread.
\since This datatype is available since SDL 3.2.0.
\sa SDL_calloc \sa SDL_GetOriginalMemoryFunctions \sa SDL_GetMemoryFunctions \sa SDL_SetMemoryFunctions