# Xhost

## Summary

From Xhost man page:

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.

See man xhost for the full info.

## Installation

Install xorg-xhost from the Official repositories.

## Usage

To provide access to an application running as sudo or su to the graphical server (aka your X session aka your computer screen), open a terminal and type as your normal user (don't su -):

    $ xhost +local:

To get things back to normal, with controlled access to the X screen:

    $ xhost -

## The 'cannot connect to X server :0.0' output

The above command xhost + will get you rid of that output, albeit momentarily; one way of getting permanently rid of this issue, among many, is to add

    xhost + >/dev/null

into your ~/.bashrc file. This way, each time you fire up the terminal, the command gets executed. If you do not yet have a .bashrc file in your home directory, it's OK to create one with just this line in it. If you do not add >/dev/null then each time you fire a terminal, you will see a non-disruptive message saying: access control disabled, clients can connect from any host, which is your confirmation that you can now sudo <your soft> without issue.

Warning: This command disables access control, meaning that any user on the system, or on your network if X is listening on the network, has access to your $DISPLAY without any authentication. This opens a security hole on your system that allows other users to launch applications (including key loggers) on your X server.
Category:

- Networking