typedef struct _WNDCLASS
{
            UINT style;
            WNDPROC lpfnWndProc;
            int cbClsExtra;
            int cbWndExtra;
            HANDLE hInstance;
            HICON hIcon;
            HCURSOR hCursor;
            HBRUSH hbrBackground;
            LPCTSTR lpszMenuName;
            LPCTSTR lpszClassName;      
}WNDCLASS;

ATOM RegisterClass(CONST WNDCLASS *lpWndClass);

HWND CreateWindow(
           LPCTSTR lpClassName,
           LPCTSTR lpWindowName,
           DWORD dwStyle,
           int x,
           int y,
           int nWidth,
           int nHeight,
           HWND hWndParent,
           HMENU hMenu,
           HANDLE hInstance,
           LPVOID lpParam
);

BOOL ShowWindow(
         HWND hWnd,
         int nCmdShow
);

BOOL UpdateWindow(
         HWND hWnd,
);