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. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)comsat.8 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD$ 34.\" 35.Dd January 21, 2010 36.Dt COMSAT 8 37.Os 38.Sh NAME 39.Nm comsat 40.Nd biff server 41.Sh SYNOPSIS 42.Nm 43.Sh DESCRIPTION 44The 45.Nm 46utility is the server process which receives reports of incoming mail 47and notifies users if they have requested this service. 48The 49.Nm 50utility receives messages on a datagram port associated with the 51.Dq biff 52service 53specification (see 54.Xr services 5 55and 56.Xr inetd 8 ) . 57The one line messages are of the form: 58.Pp 59.D1 Ar user Ns @ Ns Ar mailbox Ns - Ns Ar offset Ns Op : Ns Ar mailbox-name 60.Pp 61If the 62.Ar user 63specified is logged in to the system and the associated terminal has 64the owner execute bit turned on (by a 65.Dq Nm biff Cm y ) , 66the 67.Ar offset 68is used as a seek offset into the appropriate mailbox file and 69the first 7 lines or 560 characters of the message are printed 70on the user's terminal. 71Lines which appear to be part of 72the message header other than the 73.Dq Li From , 74.Dq Li \&To , 75.Dq Li Date , 76or 77.Dq Li Subject 78lines are not included in the displayed message. 79.Pp 80If the 81.Ar user 82specified is logged in to the system and the associated terminal has 83the group execute bit turned on (by a 84.Dq Nm biff Cm b ) , 85two bell characters 86.Tn ( ASCII 87\\007) are printed on the user's terminal. 88.Pp 89If 90.Ar mailbox-name 91omitted, standard mailbox assumed. 92.Sh FILES 93.Bl -tag -width ".Pa /var/mail/user" -compact 94.It Pa /var/run/utx.active 95to find out who is logged on and on what terminals 96.It Pa /var/mail/user 97standard mailbox 98.El 99.Sh SEE ALSO 100.Xr biff 1 , 101.Xr inetd 8 102.Sh HISTORY 103The 104.Nm 105utility appeared in 106.Bx 4.2 . 107.Sh BUGS 108The message header filtering is prone to error. 109The density of the information presented is near the theoretical minimum. 110.Pp 111Users should be notified of mail which arrives on other 112machines than the one to which they are currently logged in. 113.Pp 114The notification should appear in a separate window so it 115does not mess up the screen. 116