[TUHS] Pondering the hosts file

Hi, I'm not sure where this message best fits; TUHS, COFF, or Internet History, so please forgive me if this list is not the best location. I'm discussing the hosts file with someone and was wondering if there's any historical documentation around it's format and what should and should not be entered in the file. I've read the current man page on Gentoo Linux, but suspect that it's far from authoritative. I'm hoping that someone can point me to something more authoritative to the hosts file's format, guidelines around entering data, and how it's supposed to function. A couple of sticking points in the other discussion revolve around how many entries a host is supposed to have in the hosts file and any ramifications for having a host appear as an alias on multiple lines / entries. To whit, how correct / incorrect is the following: 192.0.2.1 host.example.net host 127.0.0.1 localhost host.example.net host -- Grant. . . . unix || die