list->update (ul_oocbs)

	update(list.s.r, tag.i4.v)

	This method is used to destructively overwrite the original contents
	of the element with the matching tag.

	list              a pointer to the list (structure of type List)
	tag               the tag to be used to update the corresponding
	                  List element

	This function returns:

	nothing

	Use of this class requires the following header files:

	list.h

	Related functions:

	create_List()     the constructor for instances of the List class

	C/C++ usage:

	#include "list.h"
	List	*list;
	int	item;
	int	tag;

	(*list->update)(list,(void *) &item,tag);