1.\" Copyright (c) 1986, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)who.1 8.2 (Berkeley) 12/30/93 29.\" 30.Dd August 30, 2020 31.Dt WHO 1 32.Os 33.Sh NAME 34.Nm who 35.Nd display who is on the system 36.Sh SYNOPSIS 37.Nm 38.Op Fl abHmqsTu 39.Op Cm am I 40.Op Ar file 41.Sh DESCRIPTION 42The 43.Nm 44utility displays information about currently logged in users. 45By default, this includes the login name, tty name, date and time of login and 46remote hostname if not local. 47.Pp 48The options are as follows: 49.Bl -tag -width indent 50.It Fl a 51Equivalent to 52.Fl bTu , 53with the exception that output is not restricted to the time and date of 54the last system reboot. 55.It Fl b 56Write the time and date of the last system reboot. 57.It Fl H 58Write column headings above the output. 59.It Fl m 60Show information about the terminal attached to standard input only. 61.It Fl q 62.Dq "Quick mode" : 63List the names and number of logged in users in columns. 64All other command line options are ignored. 65.It Fl s 66Show the name, line and time fields only. 67This is the default. 68.It Fl T 69Indicate whether each user is accepting messages. 70One of the following characters is written: 71.Pp 72.Bl -tag -width 1n -compact 73.It Li + 74User is accepting messages. 75.It Li \&- 76User is not accepting messages. 77.It Li \&? 78An error occurred. 79.El 80.It Fl u 81Show idle time for each user in hours and minutes as 82.Ar hh : Ns Ar mm , 83.Ql \&. 84if the user has been idle less than a minute, and 85.Dq Li old 86if the user has been idle more than 24 hours. 87.It Cm am I 88Equivalent to 89.Fl m . 90.El 91.Pp 92By default, 93.Nm 94gathers information from the file 95.Pa /var/run/utx.active . 96An alternate 97.Ar file 98may be specified which is usually 99.Pa /var/log/utx.log 100(or 101.Pa /var/log/utx.log.[0-6] 102depending on site policy as 103.Pa utx.log 104can grow quite large and daily versions may or may not 105be kept around after compression by 106.Xr ac 8 ) . 107The 108.Pa utx.log 109file contains a record of every login, logout, 110crash, shutdown and date change 111since 112.Pa utx.log 113was last truncated or 114created. 115.Pp 116If 117.Pa /var/log/utx.log 118is being used as the file, the user name may be empty 119or one of the special characters '|', '}' and '~'. 120Logouts produce 121an output line without any user name. 122For more information on the 123special characters, see 124.Xr getutxent 3 . 125.Sh ENVIRONMENT 126The 127.Ev COLUMNS , LANG , LC_ALL 128and 129.Ev LC_TIME 130environment variables affect the execution of 131.Nm 132as described in 133.Xr environ 7 . 134.Sh FILES 135.Bl -tag -width /var/log/utx.log.[0-6] -compact 136.It Pa /var/run/utx.active 137.It Pa /var/log/utx.log 138.It Pa /var/log/utx.log.[0-6] 139.El 140.Sh EXIT STATUS 141.Ex -std 142.Sh EXAMPLES 143Show a brief summary of who is logged in: 144.Bd -literal -offset indent 145$ who -q 146fernape root root 147# users = 3 148.Ed 149.Pp 150Show who is logged in along with the line and time fields (without the headers): 151.Bd -literal -offset indent 152$ who -s 153fernape ttyv0 Aug 26 16:23 154root ttyv1 Aug 26 16:23 155root ttyv2 Aug 26 16:23 156.Ed 157.Pp 158Show information about the terminal attached to standard input: 159.Bd -literal -offset indent 160$ who am i 161fernape Aug 26 16:24 162.Ed 163.Pp 164Show time and date of the last system reboot, whether the users accept messages 165and the idle time for each of them: 166.Bd -literal -offset indent 167$ who -a 168 - system boot Aug 26 16:23 . 169fernape - ttyv0 Aug 26 16:23 . 170root - ttyv1 Aug 26 16:23 . 171root - ttyv2 Aug 26 16:23 . 172.Ed 173.Pp 174Same as above but showing headers: 175.Bd -literal -offset indent 176$ who -aH 177NAME S LINE TIME IDLE FROM 178 - system boot Aug 26 16:23 . 179fernape - ttyv0 Aug 26 16:23 . 180root - ttyv1 Aug 26 16:23 00:01 181root - ttyv2 Aug 26 16:23 00:01 182.Ed 183.Sh SEE ALSO 184.Xr last 1 , 185.Xr users 1 , 186.Xr w 1 , 187.Xr getutxent 3 188.Sh STANDARDS 189The 190.Nm 191utility conforms to 192.St -p1003.1-2001 . 193.Sh HISTORY 194A 195.Nm 196command appeared in 197.At v1 . 198