Format of IFSHLP ??? data:
Offset	Size	Description	)
 00h	DWORD	-> DOS Swappable Data Area (see #01687,#01689)
 02h	WORD	??? offset in DOS data segment?
 04h	WORD	offset in DOS data segment of current-PSP WORD
 06h	WORD	???
 08h	WORD	???
 0Ah	WORD	???
 0Ch	DWORD	-> DOS List of Lists (see #01627)
 10h	???
SeeAlso: #01416