xhost(1)                                                    xhost(1)


       NAME
             xhost - server access control for X

       SYNOPSIS
             xhost [+-] [hostname . . .]

       DESCRIPTION
             The xhost command is used to add and delete hosts to the list
             of machines that are allowed to make connections to the X
             server.  This provides a rudimentary form of privacy control
             and security.  It is only sufficient for a workstation (single
             user) environment, although it does limit the worst abuses.
             Environments which require more sophisticated measures should
             use the hooks in the protocol for passing authentication data
             to the server.

             The server initially allows network connections only from
             programs running on the same machine or from machines listed
             in the file /etc/X*.hosts (where * is the display number of
             the server).  The xhost command is usually run either from a
             startup file or interactively to give access to other users.

          Options
             Xhost accepts the following command line options described
             below.  For security, the options that effect access control
             may only be run from the same machine as the server.  xhost
             invoked with no options prints the list of hosts allowed to
             connect (on stdout) and indicates if access control is
             enabled.

             [+] hostname
                         add hostname to the list of machines allowed to
                         connect to the X server

             - hostname  remove hostname from the list of machines allowed
                         to connect to the server.  Existing connections
                         are not broken, but new connection attempts will
                         be denied.  Attempts to remove the local host will
                         result in an access error.

             +           access control off.  Access is granted to all,
                         ignoring the allowed hosts list.

             -           access control on.  Access is restricted to the
                         allowed hosts list.



                           Copyright 1994 Novell, Inc.               Page 1

      xhost(1)                                                    xhost(1)


         Files
            /etc/X*.hosts

         Environment
            The following environment variables are used:

            DISPLAY     to get the default host and display to use

         Exit Codes
            The xhost command returns

            0     success

            1     failure

      REFERENCES
            X(1)

      NOTICES
            You can't specify a display on the command line because
            -display is a valid command line argument (indicating that you
            want to remove the machine named display from the access
            list).

            Portions of the page are derived from material which is
            copyright Massachusetts Institute of Technology.






















                          Copyright 1994 Novell, Inc.               Page 2