whoami command

whoami - print effective userid

The whoami command in Linux is an utility that displays the username of the current user running the command. It’s a quick way to confirm your identity in the terminal, especially useful in multi-user systems or when switching users with su or sudo.

Usage: whoami [OPTION]...

• OPTION: Rarely used, but there’s one flag available (--help or --version).

Examples

• Basic usage

  Running whoami prints the effective username of the current session.

  $ whoami
  • Output: alice (if your username is "alice").
  • Shows the user you’re logged in as or the effective user after privilege changes.

• Context with sudo or su

  whoami reflects the effective user, not necessarily the login user, making it handy when switching identities.

  $ sudo whoami
  • Output: root (because sudo elevates you to the root user).

  $ su -
  whoami
  • After entering the root password, output: root.

To get help related to the whoami command use --help option

$ whoami --help
Usage: whoami [OPTION]...
Print the user name associated with the current effective user ID.
Same as id -un.

      --help     display this help and exit
      --version  output version information and exit