SDL_EnableKeyRepeat (3) - Linux Manuals
SDL_EnableKeyRepeat: Set keyboard repeat rate.
NAMESDL_EnableKeyRepeat - Set keyboard repeat rate.
Enables or disables the keyboard repeat rate. delay specifies how long the key must be pressed before it begins repeating, it then repeats at the speed specified by interval. Both delay and interval are expressed in milliseconds.
Returns 0 on success and -1 on failure.