What is "whoami"

In computing, '''whoami''' is a command found on most Unix-like operating systems, Windows Vista, Windows 7, Windows 8, Windows Server 2003, and Windows Server 2008. It is a concatenation of the words "Who am I?" and prints the effective username of the current user when invoked. It has the same effect as the Unix command [[Id (Unix)|id -un]].

On Unix-like operating systems, the output of the command is slightly different from $USER because whoami outputs the username that the user is working under, whereas $USER outputs the username that was used to log in. For example, if the user logged in as John and [[su (Unix)|su]] into root, whoami displays root and echo $USER displays John. This is because the su command does not invoke a login shell by default.

The earliest versions were created in 2.9 BSD as a convenience form for who am i, the Berkeley Unix who command's way of printing just the logged in user's identity. The GNU version was written by Richard Mlynarik and is part of the GNU Core Utilities (coreutils).

The command is also available as part of the Windows 2000 Resource Kit and Windows XP SP2 Support Tools.

This command was also available as a NetWare-Command residing in the public-directory of the fileserver. It also outputs the current connections to which server the workstation is attached with which username.