Unlike the similar command "su", users must, by default, supply their own password for authentication, rather than the password of the target user. After authentication, and if the configuration file, which is typically located at codice_3, permits the user access, the system invokes the requested command. The configuration file offers detailed access permissions, including enabling commands only from the invoking terminal; requiring a password per user or group; requiring re-entry of a password every time or never requiring a password at all for a particular command line. It can also be configured to permit passing arguments or multiple commands.