xref: /freebsd/libexec/comsat/comsat.8 (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
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.Dd January 21, 2010
29.Dt COMSAT 8
30.Os
31.Sh NAME
32.Nm comsat
33.Nd biff server
34.Sh SYNOPSIS
35.Nm
36.Sh DESCRIPTION
37The
38.Nm
39utility is the server process which receives reports of incoming mail
40and notifies users if they have requested this service.
41The
42.Nm
43utility receives messages on a datagram port associated with the
44.Dq biff
45service
46specification (see
47.Xr services 5
48and
49.Xr inetd 8 ) .
50The one line messages are of the form:
51.Pp
52.D1 Ar user Ns @ Ns Ar mailbox Ns - Ns Ar offset Ns Op : Ns Ar mailbox-name
53.Pp
54If the
55.Ar user
56specified is logged in to the system and the associated terminal has
57the owner execute bit turned on (by a
58.Dq Nm biff Cm y ) ,
59the
60.Ar offset
61is used as a seek offset into the appropriate mailbox file and
62the first 7 lines or 560 characters of the message are printed
63on the user's terminal.
64Lines which appear to be part of
65the message header other than the
66.Dq Li From ,
67.Dq Li \&To ,
68.Dq Li Date ,
69or
70.Dq Li Subject
71lines are not included in the displayed message.
72.Pp
73If the
74.Ar user
75specified is logged in to the system and the associated terminal has
76the group execute bit turned on (by a
77.Dq Nm biff Cm b ) ,
78two bell characters
79.Tn ( ASCII
80\\007) are printed on the user's terminal.
81.Pp
82If
83.Ar mailbox-name
84omitted, standard mailbox assumed.
85.Sh FILES
86.Bl -tag -width ".Pa /var/mail/user" -compact
87.It Pa /var/run/utx.active
88to find out who is logged on and on what terminals
89.It Pa /var/mail/user
90standard mailbox
91.El
92.Sh SEE ALSO
93.Xr biff 1 ,
94.Xr inetd 8
95.Sh HISTORY
96The
97.Nm
98utility appeared in
99.Bx 4.2 .
100.Sh BUGS
101The message header filtering is prone to error.
102The density of the information presented is near the theoretical minimum.
103.Pp
104Users should be notified of mail which arrives on other
105machines than the one to which they are currently logged in.
106.Pp
107The notification should appear in a separate window so it
108does not mess up the screen.
109