The SRI file was different format.   There was a tool that fetched and converted from the PDP-10 scheme to the UNIX scheme - gethtable(8) or something like that.

On Thu, Mar 11, 2021 at 1:08 PM Warner Losh <> wrote:

On Thu, Mar 11, 2021 at 10:40 AM Bakul Shah <> wrote:
For each host a single line should be present with the following information:
	   Internet address
	   official host name
     The hosts file format appeared in 4.2BSD.

While this is true wrt the history of FreeBSD/Unix, I'm almost positive that BSD didn't invent it. I'm pretty sure it was picked up from the existing host file that was published by before DNS.

On Mar 11, 2021, at 9:14 AM, Grant Taylor via TUHS <> wrote:


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:    host    localhost    host

Grant. . . .
unix || die

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