{
"mode": "man",
"parameter": "who",
"section": "1",
"url": "https://www.chedong.com/phpMan.php/man/who/1/json",
"generated": "2026-06-16T15:54:06Z",
"synopsis": "who [OPTION]... [ FILE | ARG1 ARG2 ]",
"sections": {
"NAME": {
"content": "who - show who is logged on\n",
"subsections": []
},
"SYNOPSIS": {
"content": "who [OPTION]... [ FILE | ARG1 ARG2 ]\n",
"subsections": []
},
"DESCRIPTION": {
"content": "Print information about users who are currently logged in.\n",
"subsections": [
{
"name": "-a --all",
"content": "same as -b -d --login -p -r -t -T -u\n",
"flag": "-a",
"long": "--all"
},
{
"name": "-b --boot",
"content": "time of last system boot\n",
"flag": "-b",
"long": "--boot"
},
{
"name": "-d --dead",
"content": "print dead processes\n",
"flag": "-d",
"long": "--dead"
},
{
"name": "-H --heading",
"content": "print line of column headings\n\n--ips print ips instead of hostnames. with --lookup, canonicalizes based on stored IP, if\navailable, rather than stored hostname\n",
"flag": "-H",
"long": "--heading"
},
{
"name": "-l --login",
"content": "print system login processes\n",
"flag": "-l",
"long": "--login"
},
{
"name": "--lookup",
"content": "attempt to canonicalize hostnames via DNS\n",
"long": "--lookup"
},
{
"name": "-m",
"content": "",
"flag": "-m"
},
{
"name": "-p --process",
"content": "print active processes spawned by init\n",
"flag": "-p",
"long": "--process"
},
{
"name": "-q --count",
"content": "all login names and number of users logged on\n",
"flag": "-q",
"long": "--count"
},
{
"name": "-r --runlevel",
"content": "print current runlevel\n",
"flag": "-r",
"long": "--runlevel"
},
{
"name": "-s --short",
"content": "print only name, line, and time (default)\n",
"flag": "-s",
"long": "--short"
},
{
"name": "-t --time",
"content": "print last system clock change\n",
"flag": "-t",
"long": "--time"
},
{
"name": "-T -w --mesg",
"content": "add user's message status as +, - or ?\n",
"flag": "-w",
"long": "--mesg"
},
{
"name": "-u --users",
"content": "list users logged in\n",
"flag": "-u",
"long": "--users"
},
{
"name": "--message",
"content": "same as -T\n",
"long": "--message"
},
{
"name": "--writable",
"content": "same as -T\n\n--help display this help and exit\n",
"long": "--writable"
},
{
"name": "--version",
"content": "output version information and exit\n\nIf FILE is not specified, use /var/run/utmp. /var/log/wtmp as FILE is common. If ARG1 ARG2\ngiven, -m presumed: 'am i' or 'mom likes' are usual.\n",
"long": "--version"
}
]
},
"AUTHOR": {
"content": "Written by Joseph Arceneaux, David MacKenzie, and Michael Stone.\n",
"subsections": []
},
"REPORTING BUGS": {
"content": "GNU coreutils online help: \nReport any translation bugs to \n",
"subsections": []
},
"COPYRIGHT": {
"content": "Copyright © 2020 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later\n.\nThis is free software: you are free to change and redistribute it. There is NO WARRANTY, to\nthe extent permitted by law.\n",
"subsections": []
},
"SEE ALSO": {
"content": "Full documentation \nor available locally via: info '(coreutils) who invocation'\n\n\n\nGNU coreutils 8.32 January 2026 WHO(1)",
"subsections": []
}
},
"summary": "who - show who is logged on",
"flags": [
{
"flag": "-a",
"long": "--all",
"arg": null,
"description": "same as -b -d --login -p -r -t -T -u"
},
{
"flag": "-b",
"long": "--boot",
"arg": null,
"description": "time of last system boot"
},
{
"flag": "-d",
"long": "--dead",
"arg": null,
"description": "print dead processes"
},
{
"flag": "-H",
"long": "--heading",
"arg": null,
"description": "print line of column headings --ips print ips instead of hostnames. with --lookup, canonicalizes based on stored IP, if available, rather than stored hostname"
},
{
"flag": "-l",
"long": "--login",
"arg": null,
"description": "print system login processes"
},
{
"flag": "",
"long": "--lookup",
"arg": null,
"description": "attempt to canonicalize hostnames via DNS"
},
{
"flag": "-m",
"long": null,
"arg": null,
"description": ""
},
{
"flag": "-p",
"long": "--process",
"arg": null,
"description": "print active processes spawned by init"
},
{
"flag": "-q",
"long": "--count",
"arg": null,
"description": "all login names and number of users logged on"
},
{
"flag": "-r",
"long": "--runlevel",
"arg": null,
"description": "print current runlevel"
},
{
"flag": "-s",
"long": "--short",
"arg": null,
"description": "print only name, line, and time (default)"
},
{
"flag": "-t",
"long": "--time",
"arg": null,
"description": "print last system clock change"
},
{
"flag": "-w",
"long": "--mesg",
"arg": null,
"description": "add user's message status as +, - or ?"
},
{
"flag": "-u",
"long": "--users",
"arg": null,
"description": "list users logged in"
},
{
"flag": "",
"long": "--message",
"arg": null,
"description": "same as -T"
},
{
"flag": "",
"long": "--writable",
"arg": null,
"description": "same as -T --help display this help and exit"
},
{
"flag": "",
"long": "--version",
"arg": null,
"description": "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."
}
],
"examples": [],
"see_also": [],
"tldr": {
"source": "official",
"description": "Display who is logged in and related data (processes, boot time).",
"examples": [
{
"description": "Display the username, line, and time of all currently logged-in sessions",
"command": "who"
},
{
"description": "Display all available information",
"command": "who {{-a|--all}}"
},
{
"description": "Display all available information with table headers",
"command": "who {{-aH|--all --heading}}"
}
]
}
}