__glutGetMenuByNum
GlutMenu *menu = __glutGetMenuByNum(win->menuNumber);
gState.currentMenu = __glutGetMenuByNum(win->menuNumber);
GlutMenu *m = __glutGetMenuByNum(menu[button]);
GlutMenu *menu = __glutGetMenuByNum(menunum);
extern GLUTmenu * (*__glutGetMenuByNum)(int menunum);
extern GLUTmenu *__glutGetMenuByNum(int menunum);
GlutMenu *__glutGetMenuByNum(int menunum);