In the X Window System, programs connect to the X server, possibly via a computer network. Since the network may be accessible to other users, a method for forbidding access to programs run by users different from the one who is logged in is necessary.

There are five standard access control mechanisms that control whether a client application can connect to an X server. They can be grouped in three categories:

1. access based on host
2. access based on cookie
3. access based on user

Additionally, like every other network connection, tunnelling can be used. The xauth command displays and edits the authorization information used to connect to the X servers. xauth does not actually contact the X server or create the authority information.

Options:
* -b: Breaks authority file locks before proceeding. This is used to clean up stale locks.
* -f authfile: Sets the authority to use.
* -i: Overrides authority file locks.
* -q: Works in quiet mode and doesn't print unsolicited status messages.
* -v: Works in verbose mode, printing status messages indicating the results of various operations.