INT 21 - Trusted Access - NB.SYS - GET STATE                                    
	AH = 3Fh
	BX = file handle for device "$$NB$$NB"
	CX = 0002h (size of state)
	DS:DX -> buffer for state record (see #01414)
Return: CF clear if successful
	    AX = number of bytes actually read (0 if at EOF before call)
	CF set on error
	    AX = error code (05h,06h) (see #01680 at AH=59h/BX=0000h)
Program: Trusted Access is a security and access-control package by Lassen
	  Software, Inc.; NB.SYS is a device driver to prevent the user from
	  terminating CONFIG.SYS or AUTOEXEC.BAT with Ctrl-Break
SeeAlso: AH=40h"NB.SYS",AX=4101h


Format of Trusted Access state record:
Offset	Size	Description	(Table 01414)
 00h	BYTE	00h off, 01h on
 01h	BYTE	keys being disabled
		bit 0: Ctrl-Break
		bit 1: SysReq
		bit 2: Ctrl and Alt
		bit 3: Ctrl-Alt-Del
		bit 7: all keys (overrides other bits)