NAME
who - show who is logged on
SYNOPSIS
who [OPTION]... [ FILE | ARG1 ARG2 ]
DESCRIPTION
Print information about users who are currently logged in.
- -a, --all
-
same as -b -d --login -p -r -t -T -u
- -b, --boot
-
time of last system boot
- -d, --dead
-
print dead processes
- -H, --heading
-
print line of column headings
- -l, --login
-
print system login processes
- --lookup
-
attempt to canonicalize hostnames via DNS
- -m
-
only hostname and user associated with standard input
- -p, --process
-
print active processes spawned by init
- -q, --count
-
all login names and number of users logged on
- -r, --runlevel
-
print current runlevel
- -s, --short
-
print only name, line, and time (default)
- -t, --time
-
print last system clock change
- -T, -w, --mesg
-
add user's message status as +, - or ?
- -u, --users
-
list users logged in, including idle time
- --message
-
same as -T
- --writable
-
same as -T
- --help
-
display this help and exit
- --version
-
output version information and exit
If FILE is not specified, use /var/run/utmp. /var/log/wtmp as FILE is common. If ARG1 ARG2 given, -m presumed: 'am i' or 'mom likes' are usual.
AUTHOR
Written by Joseph Arceneaux, David MacKenzie, and Michael Stone.
REPORTING BUGS
Report bugs to: <[email protected]>.
Report any translation bugs to: <https://translationproject.org/team/>.
GNU coreutils home page: <https://www.gnu.org/software/coreutils/>
General help using GNU software: <https://www.gnu.org/gethelp/>
COPYRIGHT
Copyright © 2026 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO
Full documentation <https://www.gnu.org/software/coreutils/who>
or available locally via: info '(coreutils) who invocation'