comsat, in.comsat - biff server
comsat is the server process which listens for reports of incoming mail
and notifies users who have requested to be told when mail arrives. It
is invoked as needed by inetd(8C), and times out if inactive for a few
comsat listens on a datagram port associated with the biff(1) service
specification (see services(5)) for one line messages of the form
If the user specified is logged in to the system and the associated
terminal has the owner execute bit turned on (by a `biff y'), the off-
set is used as a seek offset into the appropriate mailbox file and the
first 7 lines or 560 characters of the message are printed on the
user's terminal. Lines which appear to be part of the message header
other than the From, To, Date, or Subject lines are not printed when
displaying the message.
/etc/utmp to find out who's logged on and on what terminals
biff(1), services(5), inetd(8C)
The message header filtering is prone to error.
The notification should appear in a separate window so it does not mess
up the screen.
9 September 1987 COMSAT(8C)