Definition:
- run a command with substitute user and group ID
- must enter target password
- When called with no user specified, su defaults to running an interactive shell as root.
- retains the original user’s profile and variables.
- The switched user also remains in the home directory.
- Anyone using su except the root user will be challenged for the password of the user account they are switching to.
- Using su with a hyphen following it (
su - user) enables a user to change users and launch a new shell under the context of that new user.
- This is a much better practice. Anyone using the su - except the root user will be challenged for the password of the user they are switching to.
- It is most common to switch to the root user, but any user can switch to any other user as long as they know that user’s password.
- Without a user name argument, the
su - command will assume to sign in as root
Synopsis:
su [options] [-] [user [argument...]]
List of options:
- …
-, -l, --login
- without this:
- witch user and identity but keep current profile (directory, shell,…)
- with:
- also go to target user’s home directory
- similar to relogin