instead of just UDP; an alternate protocol is specified by '-P proto'.
This is useful for finding routers that are blocking packets based on
IP protocol. New handlers can be added fairly easily to do protocol-
specific things.
(implemented better, admittedly) with a new option, '-S'. If the
maintainers of traceroute (Van?) add a -S option, we will then be in
conflict.
Also added a too-brief description of the option in the man page. Someone
with a better command of English than I at the moment should probably look
over it and rephrase it.
Reviewed by: pst, jkh
