+The
+.B \-s
+option is used for setting up the posting of messages. The line
+.IP
+.DT
+msgs: "| /usr/ucb/msgs \-s"
+.PP
+should be include in
+.I /usr/lib/aliases
+to enable posting of messages.
+.PP
+The
+.B \-c
+option is used for performing cleanup on
+.I /usr/msgs.
+An entry with the
+.B \-c
+option should be placed in
+.I /usr/lib/crontab
+to run every night. This will remove all messages over 21 days old.
+A different expiration may be specified on the command line to override
+the default.
+.PP
+Options when reading messages include: