glutSpecialFunc  -  sets the special keyboard callback for
the current window.

glutSpecialFunc
	glutSpecialFunc(func) -> None

void glutSpecialFunc(void (*func)(int key, int x, int y));

func      The new special callback function.

glutSpecialFunc sets the special keyboard callback for the
current window. The special keyboard callback is triggered
when keyboard function or directional  keys  are  pressed.
The  key  callback  parameter is a GLUT_KEY_* constant for
the special key pressed. The x and y  callback  parameters
indicate the mouse in window relative coordinates when the
key was pressed. When a new window is created, no  special
callback  is  initially registered and special key strokes
in the window are ignored.  Passing NULL  to  glutSpecial-
Func disables the generation of special callbacks.

During  a special callback, glutGetModifiers may be called
to determine the state of modifier keys when the keystroke
generating the callback occurred.

An  implementation  should  do its best to provide ways to
generate all the GLUT_KEY_* special  keys.  The  available
GLUT_KEY_* values are:

GLUT_KEY_F1
        F1 function key.

GLUT_KEY_F2
        F2 function key.

GLUT_KEY_F3
        F3 function key.

GLUT_KEY_F4
        F4 function key.

GLUT_KEY_F5
        F5 function key.

GLUT_KEY_F6
        F6 function key.

GLUT_KEY_F7
        F7 function key.

GLUT_KEY_F8
        F8 function key.

GLUT_KEY_F9
        F9 function key.

GLUT_KEY_F10
        F10 function key.

GLUT_KEY_F11
        F11 function key.

GLUT_KEY_F12
        F12 function key.

GLUT_KEY_LEFT
        Left directional key.

GLUT_KEY_UP
        Up directional key.

GLUT_KEY_RIGHT
        Right directional key.

GLUT_KEY_DOWN
        Down directional key.

GLUT_KEY_PAGE_UP
        Page up directional key.

GLUT_KEY_PAGE_DOWN
        Page down directional key.

GLUT_KEY_HOME
        Home directional key.

GLUT_KEY_END
        End directional key.

GLUT_KEY_INSERT
        Inset directional key.

Note  that the escape, backspace, and delete keys are gen-
erated as an ASCII character.

glutSpecialUpFunc,    glutKeyboardFunc,     glutMouseFunc,
glutSpaceballButtonFunc, glutButtonBoxFunc, glutTabletBut-
tonFunc, glutGetModifiers

Mark J. Kilgard (mjk@nvidia.com)