HPUX xhost[1]

 XHOST(1)                       X Version 11                        XHOST(1)

                                  Release 5



 NAME
      xhost - server access control program for X

 SYNOPSIS
      xhost [[+-]name ...]

 DESCRIPTION
      The xhost program is used to add and delete host names or user names
      to the list allowed to make connections to the X server.  In the case
      of hosts, 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 implement the user-
      based mechanism, or use the hooks in the protocol for passing other
      authentication data to the server.

      Hostnames that are followed by two colons (::) are used in checking
      DECnet connections; all other hostnames are used for TCP/IP
      connections.

      User names contain an at-sign (@).  When Secure RPC is being used, the
      network independent netname (e.g., "unix.uid@domainname") can be
      specified, or a local user can be specified with just the username and
      a trailing at-sign (e.g., "joe@").

 OPTIONS
      Xhost accepts the following command line options described below.  For
      security, the options that effect access control may only be run from
      the "controlling host".  For workstations, this is the same machine as
      the server.  For X terminals, it is the login host.

      [+]name The given name (the plus sign is optional) is added to the
              list allowed to connect to the X server.  The name can be a
              host name or a user name.

      -name   The given name is removed from the list of allowed to connect
              to the server.  The name can be a host name or a user name.
              Existing connections are not broken, but new connection
              attempts will be denied.  Note that the current machine is
              allowed to be removed; however, further connections (including
              attempts to add it back) will not be permitted.  Resetting the
              server (thereby breaking all connections) is the only way to
              allow local connections again.

      +       Access is granted to everyone, even if they aren't on the list
              (i.e., access control is turned off).

      -       Access is restricted to only those on the list (i.e., access
              control is turned on).





 Hewlett-Packard Company            - 1 -              HP-UX 9.0 August 1992






 XHOST(1)                       X Version 11                        XHOST(1)

                                  Release 5



      nothing If no command line arguments are given, a message indicating
              whether or not access control is currently enabled is printed,
              followed by the list of those allowed to connect.  This is the
              only option that may be used from machines other than the
              controlling host.

 DIAGNOSTICS
      For each name added to the access control list, a line of the form
      "name being added to access contro list" is printed.  For each name
      removed from the access control list, a line of the form "name being
      removed from access contro list" is printed.

 FILES
      /etc/X*.hosts

 SEE ALSO
      X(1), Xserver(1)

 ENVIRONMENT
      DISPLAY to get the default host and display to use.

 BUGS
      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).

      This is not really a bug, but the X server stores network addresses,
      not host names.  If somehow you change a host's network address while
      the server is still running, xhost must be used to add the new address
      and/or remove the old address.

 COPYRIGHT
      Copyright 1988, Massachusetts Institute of Technology.
      See X(1) for a full statement of rights and permissions.

 AUTHORS
      Bob Scheifler, MIT Laboratory for Computer Science,
      Jim Gettys, MIT Project Athena (DEC).
















 Hewlett-Packard Company            - 2 -              HP-UX 9.0 August 1992