Int 21 Fn 40  U - Trusted Access - Nb.sys - Set State                      [y]

   AH = 40h
   BX = handle for character device "$$NB$$NB"
   DS:DX -> state record (see #1101)
   CX ignored

Return: CF clear if successful
       AX = number of bytes actually written
   CF set on error
       AX = error code (05h,06h) (see #1366 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

See Also: AH=3Fh"NB.SYS"