INT 2F U - NETWORK REDIRECTOR - DO REDIRECTION
        AX = 111Eh
        SS = DOS DS
        STACK: WORD function to execute
                5F00h  get redirection mode
                        BL = type (03h printer, 04h disk)
                        Return: BH = state (00h off, 01h on)
                5F01h  set redirection mode
                        BL = type (03h printer, 04h disk)
                        BH = state (00h off, 01h on)
                5F02h  get redirection list entry
                        BX = redirection list index
                        DS:SI -> 16-byte local device name buffer
                        ES:DI -> 128-byte network name buffer
                        Return: must set user's BX to device type and CX to
                                stored parameter value, using AX=1218h to get
                                stack frame address
                5F03h  redirect device
                        BL = device type (see INT 21/AX=5F03h)
                        CX = stored parameter value
                        DS:SI -> ASCIZ source device name
                        ES:DI -> destination ASCIZ network path + ASCIZ passwd
                5F04h  cancel redirection
                        DS:SI -> ASCIZ device name or network path
                5F05h  get redirection list extended entry
                        BX = redirection list index
                        DS:SI -> buffer for ASCIZ source device name
                        ES:DI -> buffer for destination ASCIZ network path
                        Return: BH = status flag
                                BL = type (03h printer, 04h disk)
                                CX = stored parameter value
                                BP = NETBIOS local session number
                5F06h  similar to 5F05h???
Return: CF set on error
            AX = error code (see INT 21/AH=59h)
        STACK unchanged
Note:   called by DOS 3.1+ kernel
SeeAlso: INT 21/AX=5F01h,INT 21/AX=5F02h,INT 21/AX=5F03h