tip_private?

[Joe Pfeiffer <pfeiffer cs nmsu edu>]

In

void		 gtk_tooltips_set_tip	 (GtkTooltips     *tooltips,
					  GtkWidget	  *widget,
					  const gchar     *tip_text,
					  const gchar     *tip_private);

what is the purpose of the *tip_private parameter, and what does one
pass to it?
-- 
Joseph J. Pfeiffer, Jr., Ph.D.       Phone -- (505) 646-1605
Department of Computer Science       FAX   -- (505) 646-1002
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