who - show who is logged on


who [OPTION]... [ FILE | ARG1 ARG2 ]


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

--ips print ips instead of hostnames. with --lookup, canonicalizes based on stored IP, if available, rather than stored hostname

-l, --login
print system login processes

attempt to canonicalize hostnames via DNS

-m only hostname and user associated with stdin

-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

same as -T

same as -T

--help display this help and exit

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.


Written by Joseph Arceneaux, David MacKenzie, and Michael Stone.


Report who bugs to
GNU coreutils home page: <> General help using GNU software: <> Report who translation bugs to <>


Copyright (C) 2011 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.


The full documentation for who is maintained as a Texinfo manual. If the info and who programs are properly installed at your site, the command

info coreutils 'who invocation'

should give you access to the complete manual.