Format of Back&Forth task info buffer:
Offset	Size	Description	)
 00h 21 BYTEs	ASCIZ task name
 15h	BYTE	hotkey shift state (as for INT 16/AH=02h)
 16h	WORD	hotkey scan code (see also #00006)
 18h	WORD	program ID
Index:	hotkeys;Back&Forth
SeeAlso: #00232,#00233