typedef struct{
Uint8 type;
Uint8 state;
SDL_keysym keysym;
} SDL_KeyboardEvent;
SDL_KeyboardEvent is a member of the SDL_Event union and is used when an event of type SDL_KEYDOWN or SDL_KEYUP is reported.
The type and state actually report the same information, they just use different values to do it! A keyboard event occurs when a key is released (type=SDK_KEYUP or state=SDL_RELEASED) and when a key is pressed (type=SDL_KEYDOWN or state=SDL_PRESSED). The information on what key was pressed or released is in the keysym structure.
Repeating SDL_KEYDOWN events will occur if key repeat is enabled (see SDL_EnableKeyRepeat).
SDL_Event, SDL_keysym, SDL_EnableKeyRepeat, SDL_EnableUNICODE