xref: /freebsd/libexec/comsat/comsat.8 (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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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