NAME
	ChangeScreenBuffer -- Swap the screen's BitMap. (V39)

    SYNOPSIS
	success = ChangeScreenBuffer( Screen, ScreenBuffer )
	D0                            A0      A1

	ULONG ChangeScreenBuffer( struct Screen *, struct ScreenBuffer * );

    FUNCTION
	Performs double (or multiple) buffering on an Intuition screen
	in an Intuition-cooperative manner.  The BitMap associated
	with the supplied ScreenBuffer will be installed in the
	specified screen, if possible.  The previously-installed BitMap
	is available for re-use upon receiving a signal from
	graphics.library.  See the graphics.library autodocs for
	graphics.library/AllocDBufInfo() and graphics.library/ChangeVPBitMap()
	for details.

    INPUTS
	Screen: pointer to the screen whose bitmap is to be swapped.
	ScreenBuffer: pointer to a ScreenBuffer structure obtained from
	    AllocScreenBuffer().

    RESULT
	Returns non-zero if the operation succeeded.  Returns zero
	if the operation cannot be performed.  This function will
	fail if Intuition's state cannot permit it, for example the
	user is playing with menus or gadgets.

    NOTES
	It is not required to restore the original ScreenBuffer
	before closing the screen. Simply FreeScreenBuffer() each
	buffer (including the original and the currently-installed one)
	then close the screen.	Of course, you cannot call
	ChangeScreenBuffer() after freeing the currently-installed one.

    BUGS

    SEE ALSO
	AllocScreenBuffer(), FreeScreenBuffer(),
	graphics.library/ChangeVPBitMap()