Int 21 Fn E8  - Doubledos - Set/reset Keyboard Control Flags               [T]

   AH = E8h
   AL = program for which to set flags (00h this program, 01h other)
   DX = keyboard control flags (see #1776)

Return: DX = previous flags

Notes: disabling Ctrl-PrtSc will allow the program to intercept the keystroke;
     disabling any of the other keystrokes disables them completely
   identical to AH=F8h

See Also: AH=E1h"DoubleDOS",AH=E2h"DoubleDOS",AH=E3h"DoubleDOS"

See Also: AH=F8h"DoubleDOS"

Bitfields for DoubleDOS keyboard control flags:
Bit(s) Description (Table 1776)
 0 menu
 1 exchange
 2 entire keyboard enable/disable
 3 Ctrl-C
 4 Ctrl-PrtSc
 5 Alt/Erase
 6 Ctrl-Break
 7 Ctrl-NumLock
 8 shift-PrtSc
 9-13  undefined
 14    cancel key (clear keyboard buffer)
 15    suspend key

Note:  setting a enables the corresponding key or operatin, clearing a
     disables it