INT 21 U - Sun PC-NFS - 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.??? AX = 44E0h DS:DX -> ??? SS:BP -> stack frame (see #01589) Return: ??? Note: this function is also supported by Beame&Whiteside's BWPCNFS shim; the description presented here was derived from that shim Format of PC-NFS stack frame: Offset Size Description (Table 01589) 00h WORD -> previous stack frame 02h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. return address