structure NNode : //node for linked list of Name IX'es
 [
	next	word		//ptr to next NNode, or 0
	oldCode^0,1	word	//For family name conversion
	ix	@IXN		//a name IX
 ]

structure DNodeHdr : //header part of data node
 [
	next	word		//ptr to next DNode, or 0
	file	word		//Which file the data block is in
 ]

structure DNode : //node for linked list of data IX'es
 [
	@DNodeHdr
	ix	word IXLMax	//a data IX
 ]

manifest
 [
	lDNodeHdr = size DNodeHdr/16
 ]