SDL_UnlockYUVOverlay man page

#include "SDL.h"

void SDL_UnlockYUVOverlay(SDL_Overlay *overlay);

The opposite to SDL_LockYUVOverlay. Unlocks a previously locked overlay. An overlay must be unlocked before it can be displayed.

SDL_UnlockYUVOverlay, SDL_CreateYUVOverlay, SDL_Overlay