1.\" $OpenBSD: comsat.8,v 1.6 2007/05/31 19:19:39 jmc Exp $ 2.\" Copyright (c) 1983, 1991, 1993 3.\" The Regents of the University of California. All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. Neither the name of the University nor the names of its contributors 14.\" may be used to endorse or promote products derived from this software 15.\" without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27.\" SUCH DAMAGE. 28.\" 29.\" from: @(#)comsat.8 8.1 (Berkeley) 6/4/93 30.\" 31.Dd $Mdocdate: May 31 2007 $ 32.Dt COMSAT 8 33.Os 34.Sh NAME 35.Nm comsat 36.Nd biff server 37.Sh SYNOPSIS 38.Nm comsat 39.Sh DESCRIPTION 40.Nm 41is the server process which receives reports of incoming mail 42and notifies users if they have requested this service. 43.Nm 44receives messages on a datagram port associated with the 45.Dq biff 46service 47specification (see 48.Xr services 5 49and 50.Xr inetd 8 ) . 51The one line messages are of the form: 52.Pp 53.Dl user@mailbox-offset 54.Pp 55If the 56.Em user 57specified is logged in to the system and the associated terminal has 58the owner execute bit turned on (by a 59.Dq Li biff y ) , 60the 61.Em offset 62is used as a seek offset into the appropriate mailbox file and 63the first 7 lines or 560 characters of the message are printed 64on the user's terminal. 65Lines which appear to be part of the message header other than the 66.Dq From , 67.Dq \&To , 68.Dq Date , 69or 70.Dq Subject 71lines are not included in the displayed message. 72.Sh FILES 73.Bl -tag -width /var/run/utmp -compact 74.It Pa /var/run/utmp 75to find out who's logged on and on what terminals 76.El 77.Sh SEE ALSO 78.Xr biff 1 , 79.Xr inetd 8 80.Sh HISTORY 81The 82.Nm 83command appeared in 84.Bx 4.2 . 85.Sh BUGS 86The message header filtering is prone to error. 87The density of the information presented is near the theoretical minimum. 88.Pp 89Users should be notified of mail which arrives on other 90machines than the one to which they are currently logged in. 91.Pp 92The notification should appear in a separate window so it 93does not mess up the screen. 94