X Version 11 (Release 6.1)
server access control program for X
xhost [[+-]name . . .]
The xhost program
is used to add and delete host names
to the list 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.
xhost accepts the following command line options
For security, the options that affect 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.
displays the usegae messgae for xhost.
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.
name is removed from the list
of allowed to connect to the server.
The name can be a host name.
Existing connections are not %broken, but new
connection attempts will be denied.
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 all hosts, even if those not on the list
(that is, access control is turned off).
Access is restricted to only those hosts on the list
(that is, access control is turned on).
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 clients allowed to connect.
This is the only option that may be used from machines other than
the controlling host.
A complete name has the syntax
family:name where the families
are as follows:
inet Internet host
dnet DECnet host
nis Secure RPC network name
krb Kerberos V5 principal
local contains only one name, the empty string
The family is case insensitive. The format of the name
varies with the family.
When Secure RPC is being used, the
network independent netname (for example, ``nis:unix.uid@domainname'')
can be specified, or a local user can be specified with just the username
and a trailing at-sign (for example, ``nis:pat@'').
For backward compatibility with pre-R6 xhost,
names that contain an at-sign ``@'' are assumed to be in the nis family.
Otherwise the inet family is assumed.
default host and display number
For each name added to the access control list, a line of the
following form is printed.
For each name removed from the access control list, a line of the
following form is printed:
being added to access control list
being removed from access control list
You cannot specify a display on the command line because
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.
© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 25 April 2004