Команда su
Become super user or another user.
su [ - ] [ username [ arg ] ]
| - | Pass the environment along unchanged, as if the user actually logged in as the specified user. |
| username | The name of another username that you wish to log in as. |
| arg | Additional arguments that need to be passed through the su command. |
su - hope - would login as the user hope as if the user hope actually logged in (process all login scripts etc...)