[TUHS] Early UNIX file permission oddity

John Cowan cowan at ccil.org
Wed May 21 21:08:51 AEST 2008

Warren Toomey scripsit:

> The only possibility that I can see is, as 3rd Edition was being rewritten
> from assembly into C, the filesystem went through a stage where there
> "rwx" execute bits for user, and "rxw" execute bits for other as the CACM
> paper described, but groups had not been introduced yet. Then, the idea of
> groups was added [...]. 

I think you're probably right, but with an important caveat:

It's important to remember that 1st, 2nd, 3rd, ... represent editions of
the *manual*, and that there is no guarantee that any particular
snapshot of the system corresponds exactly to what was in any particular
manual edition.  Research Unix (as it was later called retrospectively)
was right up to the end a continuously evolving system, and the whole
concept of releases simply did not exist for it.

So when the CACM article was written, it probably specified what the
kernel was doing that particular day, without reference to any edition.

John Cowan        http://www.ccil.org/~cowan          cowan at ccil.org
Please leave your values                Check your assumptions.  In fact,
   at the front desk.                      check your assumptions at the door.
     --sign in Paris hotel                   --Cordelia Vorkosigan

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