Macintosh Terminal Pocket Guide

Name

who — stdin  stdout  - file  -- opt  --help  --version

Synopsis

who [options] [filename]

The who command lists all logged-in users, one line per login shell:

➜ who
smith    console   Sep  6 17:09
barrett  ttys000   Sep  6 17:10 (example.com)
jones    ttys001   Sep  8 20:58 (192.168.13.7)
jones    ttys002   Sep  3 05:11 (192.168.13.7)

Normally, who gets its data from the file /var/run/utmpx. The filename argument can specify a different data file, if you happen to have one in the right format.

Useful options

-H	Print a row of headings as the first line.
-u	Also print each user’s idle time at his/her terminal.
-T	Also indicate whether each user’s terminal is writable (see mesg in Messaging). A plus sign means yes, a minus sign means no, and a question mark means unknown.
-m	Display information only about yourself, i.e., the user associated with the current terminal.
-q	Quick display of usernames only, and a count of users. Much like the users command, but it adds a count.