Subject: Re: Splitting / and /usr
To: Alistair G. Crooks <email@example.com>
From: Robert Elz <kre@munnari.OZ.AU>
Date: 04/13/2000 10:36:15
Date: Wed, 12 Apr 2000 01:31:41 -0700 (PDT)
From: "Alistair G. Crooks" <firstname.lastname@example.org>
| [Off topic warning]
Ditto - but recording history sometimes has its uses...
| I believe that the topic of splitting / and /usr was discussed
| at the Glasgow University meeting of the UKUUG, which was around
It was definitely done before that.
Unfortunately, I can't find a 5th edition manual (or even a reprinted
facsimilie thereof at the minute), but the 6th edition manual for sh(1)
If the first argument [ on a command line ] is the name of an
executable file, it is invoked; otherwise the string `/bin' is
prepended to the argument. (In this way most standard commands,
which reside in `/bin', are found.) If no such command is found,
the string `/usr' is further prepended (to give `/usr/bin/command')
and another attempt is made to execute the resulting file. (Certain
lesser-used commands live in `/usr/bin'.)
The sixth edition manual is dated May 75, but the date on the sh man page
is 5/15/74 (which I interpret as the 15th of May, 1974).
For those who are new to unix (within the last 20 years) note that there
was no notion of a user settable path...
| I don't have my copy of the CACM paper to hand, so I can't
| check dates.
I have checked now, and it says nothing either way, so that is no help.
Kernighan's "Unix for Beginners" (of a generally similar vintage) gives
a diagrammatic view of the filesystem tree, in which all that exists in
/usr are user directories, though that is not really conclusive.
| I suspect that Alistair Kilgour or Zdravko Podolski could provide
| more information, or any of the Bell Labs alumni who were there.
I will see if Dennis will tell me...