NAME
	ObtainGIRPort -- Set up a RastPort for a custom gadget. (V36)

    SYNOPSIS
	RPort = ObtainGIRPort( GInfo )
	D0		       A0

	struct RastPort *ObtainGIRPort( struct GadgetInfo * );

    FUNCTION
	Sets up a RastPort for use (only) by custom gadget hook routines.
	This function must be called EACH time a hook routine needing
	to perform gadget rendering is called, and must be accompanied
	by a corresponding call to ReleaseGIRPort().

	Note that if a hook function passes you a RastPort pointer,
	e.g., GM_RENDER, you needn't call ObtainGIRPort() in that case.

    INPUTS
	A pointer to a GadgetInfo structure, as passed to each custom
	gadget hook function.

    RESULT
	A pointer to a RastPort that may be used for gadget rendering.
	This pointer may be NULL, in which case you should do no rendering.
	You may (optionally) pass a null return value to ReleaseGIRPort().

    BUGS

    SEE ALSO
	ReleaseGIRPort(), Custom Gadget documentation