1.\" $NetBSD: who.1,v 1.10 2001/12/01 16:43:28 wiz Exp $ 2.\" 3.\" Copyright (c) 1986, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)who.1 8.2 (Berkeley) 12/30/93 35.\" 36.Dd December 6, 1994 37.Dt WHO 1 38.Os 39.Sh NAME 40.Nm who 41.Nd display who is logged in 42.Sh SYNOPSIS 43.Nm 44.Op Fl mTuH 45.Op Ar file 46.Nm "" 47.Ar am i 48.Sh DESCRIPTION 49The 50.Nm 51utility displays a list of all users currently logged on, showing for 52each user the login name, tty name, the date and time of login, and 53hostname if not local. 54.Pp 55Available options: 56.Pp 57.Bl -tag -width file 58.It Fl m 59Only print information about the current terminal. This is the 60.Tn POSIX 61way of saying 62.Nm 63.Ar am i . 64.It Fl T 65Print a character after the user name indicating the state of the 66terminal line: 67.Sq + 68if the terminal is writable; 69.Sq - 70if it is not; 71and 72.Sq ? 73if a bad line is encountered. 74.It Fl u 75Print the idle time for each user. 76.It Fl H 77Write column headings above the regular output. 78.It Ar \&am I 79Returns the invoker's real user name. 80.It Ar file 81By default, 82.Nm 83gathers information from the file 84.Pa /var/run/utmp . 85An alternative 86.Ar file 87may be specified which is usually 88.Pa /var/log/wtmp 89(or 90.Pa /var/log/wtmp.[0-6] 91depending on site policy as 92.Pa wtmp 93can grow quite large and daily versions may or may not 94be kept around after compression by 95.Xr ac 8 ) . 96The 97.Pa wtmp 98file contains a record of every login, logout, 99crash, shutdown and date change 100since 101.Pa wtmp 102was last truncated or 103created. 104.El 105.Pp 106If 107.Pa /var/log/wtmp 108is being used as the file, the user name may be empty 109or one of the special characters '|', '}' and '~'. Logouts produce 110an output line without any user name. For more information on the 111special characters, see 112.Xr utmp 5 . 113.Sh FILES 114.Bl -tag -width /var/log/wtmp.[0-6] -compact 115.It Pa /var/run/utmp 116.It Pa /var/log/wtmp 117.It Pa /var/log/wtmp.[0-6] 118.El 119.Sh SEE ALSO 120.Xr last 1 , 121.Xr mesg 1 , 122.Xr users 1 , 123.Xr getuid 2 , 124.Xr utmp 5 125.Sh STANDARDS 126The 127.Nm 128utility is expected to conform to 129.St -p1003.2-92 . 130.Sh HISTORY 131A 132.Nm 133utility appeared in 134.At v6 . 135