Are there any very minimal #flex / #bison like things that will produce a self-contained parser (maybe in a single function, no libraries) for a very small #ABNF or equivalent. #libpcap has grown a slightly complex capture source definition as it moves to mainstream the #rpcap mechanism. It used to be just "eth0" or "de0", but now there are many more things. Probably a superset of URN-syntax.