INT 21 - DJ GO32.EXE 80386+ DOS extender - DOS EXTENSIONS                       
	AH = FFh
	AL = function
	    01h create file
	    02h open file
	    03h get file statistics
	    04h get time of day
	    05h set time of day
	    06h stat
	    07h system
Program: GO32.EXE is a DOS extender included as part of the 80386 port of the
	  GNU C/C++ compiler by DJ Delorie and distributed as DJGPP
SeeAlso: INT 10/AH=FFh"GO32"
                                                                                

INT 21 UP - Rational Systems DOS/4GW - API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running.  Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes.
	AH = FFh
	DH = function (00h-17h) (also see separate entries below)
	DL = subfunction or argument
Return: CF clear if valid function number
	    AX = status???
	CF set if invalid function
SeeAlso: INT 15/AX=BFDCh