Okay I talked with Richard a little (via e-mail). We agree that getprotobyname() and using the constants should be the same in functionality and speed, the use of one or the other is merely coding style. Personally, we both think the constants are prettier :).
The eight different protocols are the ones implemented in PHP- not the total number in existance (RFC 1340 has 98).
All we disagree on is using 0- Richard says that "accordning to the official unix/bsd sockets 0 is more than fine." I think that since 0 is a reserved number according to RFC 1320, and when used usually refers to IP, not one of it's sub-protocols (TCP, UDP, etc.)
