Article 3932 of alt.sys.pdp10:
Path: nntp1.ba.best.com!not-for-mail
From: inwap@best.com (Smith and O'Halloran)
Newsgroups: alt.sys.pdp10
Subject: Re: List of file extensions used on TOPS-10 and TOPS-20
Date: 24 May 1998 02:33:52 -0700
Organization: Chez INWAP (people, computers, cats)
Lines: 17
Message-ID: <6k8pi0$pso$1@shell3.ba.best.com>
References: <6k3dgj$hr9$1@shell3.ba.best.com> <6k3n99$tee$2@ligarius.ultra.net> <356725DF.1073@dvorak.amd.removethis.com>
NNTP-Posting-Host: shell3.ba.best.com
X-Trace: 896002434 14997 inwap  206.184.139.132
Xref: nntp1.ba.best.com alt.sys.pdp10:3932

In article <356725DF.1073@dvorak.amd.removethis.com>,
Clive Dawson  <clive1@dvorak.amd.removethis.com> wrote:
>BAH wrote:
>> TOPS10 had most of them documented in UUOSYM since we tended to 
>> use the same character representation for logical names, file
>> extensions, and pseudo-names  (that term doesn't sound right--it
>> was pseudo-something) for directories.
>
>You might be thinking of "pseudo devices", ...

The ersatz devices included several short names for specific directories
(UFD=[1,1], FFA=[1,2], OLD=[1,3], SYS=[1,4], NEW=[1,5], HLP=[2,5], QUE=[3,3],
REL, DOC, etc) and one non-directory logical name: OPR = a specific TTY.
	-Joe
-- 
INWAP.COM is Joe and Sally Smith, John and Chris O'Halloran and our cats
See http://www.inwap.com/ for "ReBoot", PDP-10, and Clan MacLeod.