INT 21 - DOS 3.x+ internal - GET AND SET EXTENDED CONTROL-BREAK CHECKING STATE  
	AX = 3302h
	DL = new state (00h for OFF, 01h for ON)
Return: DL = old state of extended BREAK checking
Notes:	this function does not use any of the DOS-internal stacks and may thus
	  be called at any time; one possible use is modifying Control-Break
	  checking from within an interrupt handler or TSR(Terminate and Stay Resident) A program which remains in memory after terminating in order to provide services to other programs or the user.  The name comes from the name of the DOS function call used to remain in memory after termination.
	not supported by DR DOS through version 6.0 (error code 01h);
	  newly-supported by Novell DOS 7
SeeAlso: AH=33h