Specifies the port number to listen on.
The default is a user-specific number from 8000 to 8999.
.TP 5
+.B \-r off
+Turns off DNS-SD service advertisements entirely.
+.TP 5
\fB\-r \fIsubtype[,subtype]\fR
Specifies the DNS-SD subtype(s) to advertise.
Separate multiple subtypes with a comma.