[TUHS] Quick Question: Early Filesystems and Name/Metadata Separation?

[TUHS] Quick Question: Early Filesystems and Name/Metadata Separation?

[Warren Toomey via TUHS]

Hi all, a quick question. Was Unix the first to separate
a file's name from the other file metadata (thus allowing
hard links where no filename is "better" than the others)?

Thanks, Warren

[TUHS] Quick Question: Early Filesystems and Name/Metadata Separation?

[Douglas McIlroy via TUHS]

Strachey and Stoy independently invented the same idea at essentially
the same time.
Their operating system, OS1, went into operation before Unix but
didn't get a file system until OS4, in April 1970. So Unix beat it by
six calendar months, but neither influenced the other.

OS6 was published in The Computer Journal in 1972, ahead of Unix.
Source with commentary a la Lions was available. Yet Unix got the
world's attention. Unix was compiled to machine  language for the
PDP11, while OS6 was compiled to interpreted code for the Modular One
made by Control Technologies Limited. Unix had time-sharing, while OS6
was single user. And finally Unix was American, while OS6 was British.

Later there was a similarly accidental "race" to port the two
operating systems. I'm not sure whether Wollongong or Oxford won.

Doug

[TUHS] Re: Quick Question: Early Filesystems and Name/Metadata Separation?

[Bakul Shah via TUHS]

In case anyone is further interested in Strachey & Stoy's OS6....

https://www.cs.ox.ac.uk/files/3230/PRG08.pdf

Excerpt:
A single file may be associated with different pairs of
names in different indexes, or even in the same index. This is
one form of sharing of files: two different entries point to the
same file.

The file here is equivalent to an inode. "Pairs of name" can be file
name and file type but the system doesn't care which meaning a
user attaches. There is no link count and the system has to GC.
There is even a link command!

Theoretically one can construct a directory tree (an index table).
The paper is an interesting & easy read! I wonder how much of
the OS6 & Unix designs were influenced by the respective culture's
sensibilities (British and American as well as University vs Bell Labs)!

Bakul

> On Sep 15, 2025, at 7:08 PM, Douglas McIlroy via TUHS <tuhs@tuhs.org> wrote:
> 
> Strachey and Stoy independently invented the same idea at essentially
> the same time.
> Their operating system, OS1, went into operation before Unix but
> didn't get a file system until OS4, in April 1970. So Unix beat it by
> six calendar months, but neither influenced the other.
> 
> OS6 was published in The Computer Journal in 1972, ahead of Unix.
> Source with commentary a la Lions was available. Yet Unix got the
> world's attention. Unix was compiled to machine  language for the
> PDP11, while OS6 was compiled to interpreted code for the Modular One
> made by Control Technologies Limited. Unix had time-sharing, while OS6
> was single user. And finally Unix was American, while OS6 was British.
> 
> Later there was a similarly accidental "race" to port the two
> operating systems. I'm not sure whether Wollongong or Oxford won.
> 
> Doug