INT 2F - DR DOS 6.0 TaskMAX - ENABLE/DISABLE DIRECT SWITCHING
AX = 2705h
DL = subfunction
00h disable keystrokes for switching to next/prev/specified task
01h enable
Return: nothing
Note: should only be called by a registered task manager (see AX=2704h)
SeeAlso: AX=2704h,AX=2706h