comsat(8c)
Name
comsat − biff server
Syntax
/etc/comsat
Description
The comsat command is the server process which receives reports of incoming mail and notifies users if they have requested this service. The comsat command is invoked by inetd(8c),() when it detects an incoming packet on the datagram port associated with the “biff” service specification. For further information, see services(5).() The comsat command reads the packet which is a one line messages of the form
user@mailbox-offset
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.
Restrictions
The message header filtering is prone to error.
Files
/etc/utmpto find out who’s logged on and on what terminals