Macro					Class
-----					-----
A	Internet relay			--
B	BITNET relay			--
C	CSNET relay			--
D	domain name
I	--				"Fake" (Internal) domains, i.e.
					UUCP, BITNET, CSNET.
N	--				hosts registered with the NIC
R	UUCP relay host			--
U	This host's UUCP name		UUCP aliases
V	None				List of our UUCP neighbors
W	Host to forward to for $=W	UUCP hosts on $W
X	Host to forward to for $=X	UUCP hosts on $X
Y	Host to forward to for $=Y	UUCP hosts on $Y