display-name

   Identifies the name of the X display to which you are authorizing
   access. The display name follows the supported display name
   format:

   [transport/]host:[:]server[.screen]

   This format enables you to use a single X authority file to
   grant varying levels of access to different X display servers
   and connection families.

   For example, the following entries grant access to the local
   display server on node HUBBUB and the remote display server on
   node ZEPHYR via the DECnet transport:

local/HUBBUB:0 MIT-MAGIC-COOKIE-1 cfcc5ef98f9718f90154f355c0ae9f62
decnet/ZEPHYR::0 MIT-MAGIC-COOKIE-1 cfcc5ef98f9718f90154f355c0ae9f62

   o  [transport/]
      Identifies the network transport used to connect to an X
      display server. See the DECwindows Motif documentation for
      a list of the supported transport values. If a transport value
      is not specified, the default value is interpreted from the
      format of the remaining portions of the display-name entry,
      for example:

         Host address and one colon (116.94.24.187:0) (TCP/IP)
         Two colons (::0 or ZEPHYR::0) (DECnet)
         No host name or address and one colon (:0) (local)

   o  host[:]
      Identifies the name of the host system where the X display
      server is located. A value of 0 is interpreted as the local
      host, which is the default. The type of host is determined
      by the transport value. See the DECwindows documentation for
      examples of valid host name and address formats.

   o  :server
      Identifies the server. This value is required and must be
      preceded by a single colon (:). Typically the value for a
      single-server system is :0. If you are specifying a display
      on a multi-server system (such as when using a proxy server),
      additional values may apply depending on the number of servers
      in the configuration. If you have specified a display device
      (with the SET DISPLAY command), the server portion of the
      entry is assumed from the device specification.

   o  [.screen]
      Identifies the screen. On OpenVMS Alpha and OpenVMS I64
      systems, the screen value is not held in the X authority file
      and is ignored when included in a command. All screens on a
      single server have the same authorization.