  This material was originally written and compiled by Wietse Venema at
  Eindhoven University of Technology, The Netherlands, in 1990, 1991,
  1992, 1993, 1994 and 1995.

  Redistribution and use in source and binary forms are permitted
  provided that this entire copyright notice is duplicated in all such
  copies.

  This software is provided "as is" and without any expressed or implied
  warranties, including, without limitation, the implied warranties of
  merchantability and fitness for any particular purpose.