INT 7C - SK-UPPS Data Link Interface 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. - RELEASE BUFFER
	AX = 0005h
	ES:BX -> Mbuf (see #03847)
Return: nothing
SeeAlso: AX=0004h