1.\" Copyright (c) 1983, 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.\" @(#)comsat.8 8.1 (Berkeley) 6/4/93 29.\" $FreeBSD: src/libexec/comsat/comsat.8,v 1.14 2005/02/13 23:45:48 ru Exp $ 30.\" $DragonFly: src/libexec/comsat/comsat.8,v 1.3 2006/02/17 19:33:31 swildner Exp $ 31.\" 32.Dd August 9, 2002 33.Dt COMSAT 8 34.Os 35.Sh NAME 36.Nm comsat 37.Nd biff server 38.Sh SYNOPSIS 39.Nm 40.Sh DESCRIPTION 41The 42.Nm 43utility is the server process which receives reports of incoming mail 44and notifies users if they have requested this service. 45The 46.Nm 47utility receives messages on a datagram port associated with the 48.Dq biff 49service 50specification (see 51.Xr services 5 52and 53.Xr inetd 8 ) . 54The one line messages are of the form: 55.Pp 56.D1 Ar user Ns @ Ns Ar mailbox Ns - Ns Ar offset Ns Op : Ns Ar mailbox-name 57.Pp 58If the 59.Ar user 60specified is logged in to the system and the associated terminal has 61the owner execute bit turned on (by a 62.Dq Nm biff Cm y ) , 63the 64.Ar offset 65is used as a seek offset into the appropriate mailbox file and 66the first 7 lines or 560 characters of the message are printed 67on the user's terminal. 68Lines which appear to be part of 69the message header other than the 70.Dq Li From , 71.Dq Li \&To , 72.Dq Li Date , 73or 74.Dq Li Subject 75lines are not included in the displayed message. 76.Pp 77If the 78.Ar user 79specified is logged in to the system and the associated terminal has 80the group execute bit turned on (by a 81.Dq Nm biff Cm b ) , 82two bell characters 83.Tn ( ASCII 84\\007) are printed on the user's terminal. 85.Pp 86If 87.Ar mailbox-name 88omitted, standard mailbox assumed. 89.Sh FILES 90.Bl -tag -width ".Pa /var/mail/user" -compact 91.It Pa /var/run/utmp 92to find out who is logged on and on what terminals 93.It Pa /var/mail/user 94standard mailbox 95.El 96.Sh SEE ALSO 97.Xr biff 1 , 98.Xr inetd 8 99.Sh HISTORY 100The 101.Nm 102utility appeared in 103.Bx 4.2 . 104.Sh BUGS 105The message header filtering is prone to error. 106The density of the information presented is near the theoretical minimum. 107.Pp 108Users should be notified of mail which arrives on other 109machines than the one to which they are currently logged in. 110.Pp 111The notification should appear in a separate window so it 112does not mess up the screen. 113