WHO(1) User Commands WHO(1)

# [NAME](#NAME)

who - show who is logged on

# [SYNOPSIS](#SYNOPSIS)

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

# [DESCRIPTION](#DESCRIPTION)

Print information about users who are currently logged in.

[**-a, --all**](#a,)

same as **-b** **-d** **--login** **-p** **-r** **-t** **-T** **-u**

[**-b, --boot**](#b,)

time of last system boot

[**-d, --dead**](#d,)

print dead processes

[**-H, --heading**](#H,)

print line of column headings

[**-l, --login**](#l,)

print system login processes

[**--lookup**](#lookup)

attempt to canonicalize hostnames via DNS

[**-m**](#m)

only hostname and user associated with standard input

[**-p, --process**](#p,)

print active processes spawned by init

[**-q, --count**](#q,)

all login names and number of users logged on

[**-r, --runlevel**](#r,)

print current runlevel

[**-s, --short**](#s,)

print only name, line, and time (default)

[**-t, --time**](#t,)

print last system clock change

[**-T, -w, --mesg**](#T,)

add user's message status as +, - or ?

[**-u, --users**](#u,)

list users logged in, including idle time

[**--message**](#message)

same as **-T**

[**--writable**](#writable)

same as **-T**

[**--help**](#help)

display this help and exit

[**--version**](#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](#AUTHOR)

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

# [REPORTING BUGS](#REPORTING_BUGS)

Report bugs to: <bug-coreutils@gnu.org>.  
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)

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](#SEE_ALSO)

Full documentation <https://www.gnu.org/software/coreutils/who>  
or available locally via: info '(coreutils) who invocation'

October 2026 GNU coreutils 9.12

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Document: who(1) from coreutils 9.12-r7 (Chainguard OS)
Source: https://git.savannah.gnu.org/git/coreutils.git