From: wkt@tuhs.org (Warren Toomey)
Subject: [TUHS] Early non-Unix filesystems?
Date: Fri, 18 Mar 2016 10:48:32 +1000 [thread overview]
Message-ID: <20160318004832.GA18245@minnie.tuhs.org> (raw)
It's a bit off-topic, but what were non-Unix filesystems like around 1969-1970?
The PDP-7 filesystem has i-nodes (file metadata) and filenames separate
from the i-nodes. This allows hard links and thus a non-tree structured
filesystem.
This has always struck me to be one of the most important features of
the Unix filesystem: names separated from the rest of the file metadata,
and arbitrary hard links so that there is no preferred filename.
Were these features in other contemporaneous filesystems?
As a side note, the PDP-7 kernel knows about the top-level directory ("dd")
but it is agnostic to the concept of "." and "..". What that means is
that you can build a filesystem with "." and ".." links and the kernel
will deal with them as per all other links. But you can also build a
filesystem without "." or ".." and the kernel doesn't care.
There's not enough evidence (source code, papers, anecdotes) to confirm
or deny the presence of "." in the PDP-7 code that Norman scanned for us.
".." does seem to exist as it is mentioned in one source file, ds.s.
It's an intruiging mystery.
Cheers, Warren
next reply other threads:[~2016-03-18 0:48 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-18 0:48 Warren Toomey [this message]
2016-03-18 2:49 ` Greg 'groggy' Lehey
2016-03-18 3:59 ` John Cowan
2016-03-18 5:11 ` Warren Toomey
2016-03-18 17:45 ` John Cowan
2016-03-18 8:00 ` Dave Horsfall
2016-03-18 8:42 ` Peter Jeremy
2016-03-18 13:04 ` Clem Cole
2016-03-18 17:12 ` scj
2016-03-18 17:45 ` Random832
2016-03-18 18:02 ` scj
2016-03-21 14:11 ` Dave Horsfall
2016-03-21 21:43 ` Greg 'groggy' Lehey
2016-03-21 22:57 ` scj
2016-03-21 23:05 ` Lyndon Nerenberg
2016-03-22 0:27 ` Greg 'groggy' Lehey
2016-03-23 22:46 ` Dave Horsfall
2016-03-24 0:32 ` Ron Natalie
2016-03-24 0:43 ` Milo Velimirovic
2016-03-24 0:47 ` Ron Natalie
2016-03-24 1:05 ` Clem Cole
2016-03-23 1:28 ` Dave Horsfall
2016-03-23 1:51 ` Milo Velimirovic
2016-03-23 6:49 ` Greg 'groggy' Lehey
2016-03-23 7:02 ` Peter Jeremy
2016-03-23 7:12 ` Greg 'groggy' Lehey
2016-03-23 13:54 ` Ron Natalie
2016-03-23 16:28 ` John Cowan
2016-03-23 8:20 ` Dave Horsfall
2016-03-21 11:07 ` Tony Finch
2016-03-21 12:06 ` John Cowan
2016-03-22 0:13 ` Greg 'groggy' Lehey
2016-03-22 0:48 ` John Cowan
2016-03-18 17:01 ` Pat Barron
2016-03-22 5:21 ` shawn wilson
2016-03-23 0:54 ` Clem Cole
2016-03-23 1:07 ` Clem Cole
[not found] <mailman.1.1458266402.23080.tuhs@minnie.tuhs.org>
2016-03-18 2:13 ` Johnny Billquist
2016-03-18 2:36 ` Charles Anthony
2016-03-18 2:26 Noel Chiappa
2016-03-22 0:56 Doug McIlroy
2016-03-23 1:58 Doug McIlroy
[not found] <mailman.1.1458784801.4499.tuhs@minnie.tuhs.org>
2016-03-24 10:17 ` Johnny Billquist
2016-03-24 11:35 ` Ron Natalie
2016-03-24 11:37 ` Johnny Billquist
2016-03-24 22:50 ` Peter Jeremy
2016-03-24 23:06 ` Johnny Billquist
[not found] ` <9CBDF635-2FC9-4855-8419-0413EC0336A7@centurytel.net>
2016-03-25 0:35 ` Johnny Billquist
2016-03-27 0:48 ` Dave Horsfall
2016-03-24 19:13 Nemo
2016-03-24 19:54 ` Milo Velimirović
2016-03-26 21:05 ` Ronald Natalie
2016-03-26 21:34 ` Charles Anthony
2016-03-26 22:09 ` Ronald Natalie
2016-03-28 20:32 ` scj
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