xref: /dragonfly/libexec/comsat/comsat.8 (revision 335b9e93)
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28.\"     @(#)comsat.8	8.1 (Berkeley) 6/4/93
29.\" $FreeBSD: head/libexec/comsat/comsat.8 262136 2014-02-17 22:27:32Z brueffer $
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31.Dd September 10, 2019
32.Dt COMSAT 8
33.Os
34.Sh NAME
35.Nm comsat
36.Nd biff server
37.Sh SYNOPSIS
38.Nm
39.Sh DESCRIPTION
40The
41.Nm
42utility is the server process which receives reports of incoming mail
43and notifies users if they have requested this service.
44The
45.Nm
46utility receives messages on a datagram port associated with the
47.Dq biff
48service
49specification (see
50.Xr services 5
51and
52.Xr inetd 8 ) .
53The one line messages are of the form:
54.Pp
55.D1 Ar user Ns @ Ns Ar mailbox Ns - Ns Ar offset Ns Op : Ns Ar mailbox-name
56.Pp
57If the
58.Ar user
59specified is logged in to the system and the associated terminal has
60the owner execute bit turned on (by a
61.Dq Nm biff Cm y ) ,
62the
63.Ar offset
64is used as a seek offset into the appropriate mailbox file and
65the first 7 lines or 560 characters of the message are printed
66on the user's terminal.
67Lines which appear to be part of
68the message header other than the
69.Dq Li From ,
70.Dq Li \&To ,
71.Dq Li Date ,
72or
73.Dq Li Subject
74lines are not included in the displayed message.
75.Pp
76If the
77.Ar user
78specified is logged in to the system and the associated terminal has
79the group execute bit turned on (by a
80.Dq Nm biff Cm b ) ,
81two bell characters
82.Tn ( ASCII
83\\007) are printed on the user's terminal.
84.Pp
85If
86.Ar mailbox-name
87omitted, standard mailbox assumed.
88.Sh FILES
89.Bl -tag -width ".Pa /var/mail/user" -compact
90.It Pa /var/run/utmpx
91to find out who is logged on and on what terminals
92.It Pa /var/mail/user
93standard mailbox
94.El
95.Sh SEE ALSO
96.Xr biff 1 ,
97.Xr inetd 8
98.Sh HISTORY
99The
100.Nm
101utility appeared in
102.Bx 4.2 .
103.Sh BUGS
104The message header filtering is prone to error.
105The density of the information presented is near the theoretical minimum.
106.Pp
107Users should be notified of mail which arrives on other
108machines than the one to which they are currently logged in.
109.Pp
110The notification should appear in a separate window so it
111does not mess up the screen.
112