Use the XAUTH ADD and XAUTH REMOVE commands to add entries to or
    delete entries from an X authority file.

    If you have created a display device (using the SET DISPLAY
    command), you can specify the device name on the xauth command
    line to insert or remove entries related to the display device.
    Typically, the X authority file entry for a display device
    corresponds to the display server specified by the SET DISPLAY
    command. However, if the SET DISPLAY command specifies that
    a proxy server be used, the file entry pertains to that proxy
    server.

    For example, the following X authority file has a single
    entry for the LOCAL transport on node ZEPHYR. To use the same
    authorization key for the DECnet transport and to specify
    that Kerberos be used when connecting to remote node HUBBUB,
    you could add the following entries to the X authority file
    UNTRUSTED.DECW$XAUTH:

    $  XAUTH -f UNTRUSTED.DECW$XAUTH
    Using authority file untrusted.decw$xauth

    xauth>  LIST
    local/ZEPHYR:0  MIT-MAGIC-COOKIE-1  cfcc5ef98f9718f90154f355c0ae9f62

    xauth>  ADD ::0 . cfcc5ef98f9718f90154f355c0ae9f62
    xauth>  ADD HUBBUB::0 MIT-KERBEROS-5 ""

    xauth>  LIST
    local/ZEPHYR:0  MIT-MAGIC-COOKIE-1  cfcc5ef98f9718f90154f355c0ae9f62
    decnet/ZEPHYR::0  MIT-MAGIC-COOKIE-1  cfcc5ef98f9718f90154f355c0ae9f62
    decnet/HUBBUB::0  MIT-KERBEROS-5

    xauth> EXIT
    Writing X authority file untrusted.decw$xauth

    Client applications running on systems in the same cluster
    share a single X authority file. As a result, in cluster
    configurations, adding an entry for the DECnet transport to the
    local system grants client applications running on other nodes in
    the cluster access to that system.

    To discontinue remote access to HUBBUB, you could use the XAUTH
    REMOVE command to remove the entry, as follows:

    $  XAUTH -f UNTRUSTED.DECW$XAUTH
    Using authority file untrusted.decw$xauth

    xauth> REMOVE HUBBUB::0
    1 entries removed

    xauth> LIST
    local/ZEPHYR:0  MIT-MAGIC-COOKIE-1  cfcc5ef98f9718f90154f355c0ae9f62
    decnet/ZEPHYR::0  MIT-MAGIC-COOKIE-1  cfcc5ef98f9718f90154f355c0ae9f62

    xauth> EXIT
    Writing X authority file untrusted.decw$xauth