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.Dd August 30, 2020 29.Dt WHO 1 30.Os 31.Sh NAME 32.Nm who 33.Nd display who is on the system 34.Sh SYNOPSIS 35.Nm 36.Op Fl abHmqsTu 37.Op Cm am I 38.Op Ar file 39.Sh DESCRIPTION 40The 41.Nm 42utility displays information about currently logged in users. 43By default, this includes the login name, tty name, date and time of login and 44remote hostname if not local. 45.Pp 46The options are as follows: 47.Bl -tag -width indent 48.It Fl a 49Equivalent to 50.Fl bTu , 51with the exception that output is not restricted to the time and date of 52the last system reboot. 53.It Fl b 54Write the time and date of the last system reboot. 55.It Fl H 56Write column headings above the output. 57.It Fl m 58Show information about the terminal attached to standard input only. 59.It Fl q 60.Dq "Quick mode" : 61List the names and number of logged in users in columns. 62All other command line options are ignored. 63.It Fl s 64Show the name, line and time fields only. 65This is the default. 66.It Fl T 67Indicate whether each user is accepting messages. 68One of the following characters is written: 69.Pp 70.Bl -tag -width 1n -compact 71.It Li + 72User is accepting messages. 73.It Li \&- 74User is not accepting messages. 75.It Li \&? 76An error occurred. 77.El 78.It Fl u 79Show idle time for each user in hours and minutes as 80.Ar hh : Ns Ar mm , 81.Ql \&. 82if the user has been idle less than a minute, and 83.Dq Li old 84if the user has been idle more than 24 hours. 85.It Cm am I 86Equivalent to 87.Fl m . 88.El 89.Pp 90By default, 91.Nm 92gathers information from the file 93.Pa /var/run/utx.active . 94An alternate 95.Ar file 96may be specified which is usually 97.Pa /var/log/utx.log 98(or 99.Pa /var/log/utx.log.[0-6] 100depending on site policy as 101.Pa utx.log 102can grow quite large and daily versions may or may not 103be kept around after compression by 104.Xr ac 8 ) . 105The 106.Pa utx.log 107file contains a record of every login, logout, 108crash, shutdown and date change 109since 110.Pa utx.log 111was last truncated or 112created. 113.Pp 114If 115.Pa /var/log/utx.log 116is being used as the file, the user name may be empty 117or one of the special characters '|', '}' and '~'. 118Logouts produce 119an output line without any user name. 120For more information on the 121special characters, see 122.Xr getutxent 3 . 123.Sh ENVIRONMENT 124The 125.Ev COLUMNS , LANG , LC_ALL 126and 127.Ev LC_TIME 128environment variables affect the execution of 129.Nm 130as described in 131.Xr environ 7 . 132.Sh FILES 133.Bl -tag -width /var/log/utx.log.[0-6] -compact 134.It Pa /var/run/utx.active 135.It Pa /var/log/utx.log 136.It Pa /var/log/utx.log.[0-6] 137.El 138.Sh EXIT STATUS 139.Ex -std 140.Sh EXAMPLES 141Show a brief summary of who is logged in: 142.Bd -literal -offset indent 143$ who -q 144fernape root root 145# users = 3 146.Ed 147.Pp 148Show who is logged in along with the line and time fields (without the headers): 149.Bd -literal -offset indent 150$ who -s 151fernape ttyv0 Aug 26 16:23 152root ttyv1 Aug 26 16:23 153root ttyv2 Aug 26 16:23 154.Ed 155.Pp 156Show information about the terminal attached to standard input: 157.Bd -literal -offset indent 158$ who am i 159fernape Aug 26 16:24 160.Ed 161.Pp 162Show time and date of the last system reboot, whether the users accept messages 163and the idle time for each of them: 164.Bd -literal -offset indent 165$ who -a 166 - system boot Aug 26 16:23 . 167fernape - ttyv0 Aug 26 16:23 . 168root - ttyv1 Aug 26 16:23 . 169root - ttyv2 Aug 26 16:23 . 170.Ed 171.Pp 172Same as above but showing headers: 173.Bd -literal -offset indent 174$ who -aH 175NAME S LINE TIME IDLE FROM 176 - system boot Aug 26 16:23 . 177fernape - ttyv0 Aug 26 16:23 . 178root - ttyv1 Aug 26 16:23 00:01 179root - ttyv2 Aug 26 16:23 00:01 180.Ed 181.Sh SEE ALSO 182.Xr last 1 , 183.Xr users 1 , 184.Xr w 1 , 185.Xr getutxent 3 186.Sh STANDARDS 187The 188.Nm 189utility conforms to 190.St -p1003.1-2001 . 191.Sh HISTORY 192A 193.Nm 194command appeared in 195.At v1 . 196