Subject: Origins of Hierarchical Filesystems

From: "Robert Krten" <[email-masked]>
Date: Tue Mar 11 21:40:00 2003

Hi folks,

writing a chapter on filesystems, and was wondering if anyone knows the
origins of the hierarchical filesystem (and no, it wasn't MS-DOS 2.0 :-))

I know TOPS-10 and friends used it, so it's got to be at least that old.

Any takers?

I'm looking for a ballpark year and the name of the OS and company...

Probably just reply to me only; I'll be happy to summarize for the group.

Thanks!
-RK

--
Looking for Digital Equipment Corp. PDP-1 through PDP-15 minicomputers!
Robert Krten, PARSE Software Devices +1 613 599 8316.
Realtime Systems Architecture, Consulting and Training at www.parse.com

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From: "Andy Holt" <[email-masked]>
Date: Fri Apr 4 12:38:55 2003

Sorry to be so slow in responding to this - I tried to find some good
references but got nowhere definite.

My best impression is that the concept first came to light in the mid '60s
... probably inspired by the structure of the Algol 60 programming language.

Likely first appeared in "research" operating systems in continental europe
(people like Dijkstra and Wirth were much more keen on recursion than most
UK or US researchers) and then appeared in better-known systems like Multics
and George 3.
Some systems had a limited number of levels of hierarchy - typically
system/user and sometimes one more level below. Often this was done by
"cheating" with what was really a single level directory. I'm not sure how
Atlas and Titan did it. I'm also not convinced that the early versions of
TOPS 10 had anything better than this ... similarly for the GE time sharing
system that eventually evolved into GCOS.

Andy

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]]On
> Behalf Of Robert Krten
> Sent: 11 March 2003 03:41
> To: [email-masked]
> Subject: Origins of Hierarchical Filesystems
>
>
> Hi folks,
>