Ruby interface to LBL Packet Capture library (libpcap).  This library
also includes classes to access packet header fields.

It is much easier to code in Ruby/Pcap than to code in C and use
libpcap directly.

Author:	Masaki Fukushima <fukusima@goto.info.waseda.ac.jp>
WWW:	http://www.goto.info.waseda.ac.jp/~fukusima/ruby/pcap-e.html