Function 4409h          Is Drive Remote                              DOS 3.1+

    Determines whether the specified drive is local (attached to the
    computer running the program) or remote (on a network server).

        Entry   AX = 4409h
                BL = Drive number (0 = default, 1 = A, etc.)

        Return  DX bit 12 = 1   If drive is remote
                AX changed
                or
                AX = Error code, if CF is set
                     | 01h Invalid function
                     | 0Fh Invalid drive

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    If bit 12 of DX is set, the drive is remote (for example, if it
    represents a network connection) or is a non-standard file system
    (for example, CD-ROM); the other bits in DX are zero.

    If bit 12 of DX is zero, the drive is not a network drive, and the
    bits in the DX register have the following meaning:

                Bit     Description
                1       1 = Drive uses 32-bit sector addressing
                6       1 = Drive accepts Generic IOCTL for Block
                            Devices, Get Logical Drive Map, and Set
                            Logical Drive Map (functions 440dh, 440eh,
                            and 440fh)
                7       1 = Drive accepts Query IOCTL Device (function
                            4411h)
                9       1 = Drive is local but shared by other
                            computers in the network.
                11      1 = Drive accepts Does Device Use Removable
                            Media (function 4408h)
                13      1 = Drive requires media descriptor in FAT
                14      1 = Drive accepts Receive Control Data from
                            Block Device and Send Control Data to
                            Block Device (functions 4404h and 4405h)
                15      1 = Substitution drive (for example, set by
                            the SUBST command)
                All other bits zero