How do I List Unix users?

List Logged In Unix Users

Unix has many commands to list users who are logged in.

These commands include `w`, `who`, and `users`:



$ w

 9:51PM  up 99 days,  5:39, 2 users, load averages: 0.83, 0.90, 0.90

USER             TTY      FROM              LOGIN@  IDLE WHAT

will             p0       c-66-164-235-73.  8:11AM     - w

spencer          p3       c-66-164-235-73.  8:26PM  1:24 pine



$ who

will             ttyp0    Jul 26 08:11 (66.164.235.73)

spencer          ttyp3    Jul 26 20:26 (66.164.235.73)



$ users

spencer will

List All Unix Users

To list all users on a Unix system, even the ones who are not logged in, look at the /etc/password file.



$ cat /etc/passwd

...

george:*:1009:1009:George Washington:/home/george:/usr/bin/bash

tom:*:1016:1016:Thomas Jefferson:/home/tom:/usr/bin/bash

al:*:1017:1017:Alexander Hamilton:/home/alex:/usr/bin/bash

...

You can use the `cut` command to only see one field from the password file.

For example, to just see the Unix user names, use the command "$ cat /etc/passwd | cut -d: -f1".



$ cat /etc/passwd | cut -d: -f1

...

george

tom

al

...

Or, to only see the GECOS field (i.e. the account holders real name), try this:



$ cat /etc/passwd | cut -d: -f5

...

George Washinton

Thomas Jefferson

Alexander Hamilton

...

Note that you will also see Unix system accounts, such as "root", "bin", and "daemon" in the /etc/passwd file. These system accounts are not Unix users.

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