COMSAT(8)               FreeBSD System Manager's Manual              COMSAT(8)

NAME
     comsat - biff server

SYNOPSIS
     comsat

DESCRIPTION
     The comsat utility is the server process which receives reports of
     incoming mail and notifies users if they have requested this service.
     The comsat utility receives messages on a datagram port associated with
     the "biff" service specification (see services(5) and inetd(8)).  The one
     line messages are of the form:

           user@mailbox-offset[:mailbox-name]

     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 offset
     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 included in the
     displayed message.

     If the user specified is logged in to the system and the associated
     terminal has the group execute bit turned on (by a "biff b"), two bell
     characters (ASCII \007) are printed on the user's terminal.

     If mailbox-name omitted, standard mailbox assumed.

FILES
     /var/run/utx.active
                         to find out who is logged on and on what terminals
     /var/mail/user      standard mailbox

SEE ALSO
     biff(1), inetd(8)

HISTORY
     The comsat utility appeared in 4.2BSD.

BUGS
     The message header filtering is prone to error.  The density of the
     information presented is near the theoretical minimum.

     Users should be notified of mail which arrives on other machines than the
     one to which they are currently logged in.

     The notification should appear in a separate window so it does not mess
     up the screen.

FreeBSD 13.1-RELEASE-p6        January 21, 2010        FreeBSD 13.1-RELEASE-p6