INT 2F CU - IFSFUNC.EXE (DOS 4.x only) - IFSsee Installable File System IOCTL
	AX = 112Fh
	SS = DOS DS
	STACK: WORD function in low byte
		00h ???
		    DS:SI -> Current Directory StructureThe data record used by DOS to keep track of the current directory on a drive; whether the drive is valid, network, SUBSTituted, or JOINed; and other pertinent information.  See also INT 21h Function 52h.???
		    CL = drive (1=A:)
		01h ???
		    DS:SI -> ???
		    CL = file handle???
		02h ???
		    DS:SI -> Current Directory StructureThe data record used by DOS to keep track of the current directory on a drive; whether the drive is valid, network, SUBSTituted, or JOINed; and other pertinent information.  See also INT 21h Function 52h.???
		    DI = ???
		    CX = drive (1=A:)
	???
Return: CF set on error
	    AX = DOS error code (see #01680 at INT 21/AH=59h/BX=0000h)
	CF clear if successful
Note:	this function is called by the DOS 4.0 kernel
SeeAlso: INT 21/AH=6Bh