Int 2Fh / B706h         Get APPEND.EXE Modes Flag                    DOS 4.0+

    Returns the current operation modes for the APPEND command.

        Entry   AX = 0B706h

        Return  BX = APPEND operation modes

        BX bit  Meaning
        0       APPEND is enabled.
        12      APPEND applies appended directories to file requests
                that already specify a drive.
        13      APPEND applies appended directories to file requests
                that already specify a path (set if /PATH switch is
                on).
        14      APPEND stores the appended directories in the APPEND
                environment variable (set if /e switch specified).
        15      APPEND applies appended directories to functions such
                as Load and Execute Program (Int 21h/4B00h), and Find
                First File (Int 21h/4Eh) (set if /x switch is on).
        All other bits are reserved (0).