Hi list,

Not no off-topic, but a little unix history oriented question.

In hier(7) OpenBSD describe /usr as "Contains the majority of user utilities
and applications".

In
http://www.usna.edu/Users/cs/delooze/teaching/IC221/Lectures/LN02/class02.html
they
say that /usr "Stands for Unix System Resources. Contains system utilities".

In wikipedia they say /usr is "*Secondary hierarchy* for read-only user
data; contains the majority of
(multi-<http://en.wikipedia.org/wiki/Multi-user>)user
utilities and applications"
http://en.wikipedia.org/wiki/Filesystem_Hierarchy_Standard

So my doubt is: Is "usr" an abbreviation of "user"? If that is so (as as
hier(7) can be understood), why /usr contains mainly "system resources" and
not "user resources"? In fact only root has w permission inside /usr, so it
seems more a system directory. I know that a system directory contains
resources for the user, but, just for curiosity, what is the origin of this
directory name? A user place o a unix system place?

Thanks.

Harrell

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When you boot into single user mode, what is available?
/ which includes /bin /sbin /etc /dev

This includes all the basic system utilities.

If you want fancier stuff, you need to mount /usr /home /var etc

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On Sat, 1 May 2010 22:52:54 +0200 Harrell

In many situations knowing where a name comes from is really helpful,
but in other situations, knowing where a name came from is completely
misleading since over time, definitions change. The name of the "/usr"
directory is the latter. 

At one point in time in the ancient past, the /usr directory is where
user directories were once stored, but over time the usage of this
directory changed. The claim of 'usr' being an abbreviation for Unix
System Resources is a "backronym," (i.e. an abbreviation created
after the fact).

	jcr

-- 
The OpenBSD Journal - http://www.undeadly.org

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Chapter 4 of Greg Lehey's Porting Unix Software

 http://www.lemis.com/grog/Documentation/PUS/

has the following to say about the /usr directory:

 This directory used to be the other file system on a UNIX machine.  In
 the System V ABI it has lost most of its importance.  The ABI states
 uses only for /usr/bin and /usr/share, and the name /usr has lost its
 original meaning: the ABI specifies /usr only as a location for system
 files that users may wish to access.

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Your question has already been answered, but in case you are looking
for documentation, here's Dennis Ritchie (as in K&R C)in the 1978
(July-August) Bell System Technical Journal, pp. 1953-4:

  "It is common for the totality of user files to be too voluminous
  for a given device.  It is then impossible for the directories of
  all users to be members of the same directory, say /usr.  Instead
  they must be split into groups, say /usr1 and /usr2;"

And Steve Bourne (as in Bourne shell), same issue, p. 1981, referring
to user "fred" setting the $PATH environment variable:

  PATH=:/usr/fred/bin:/bin:/usr/bin

Finally, looking at our old 1984 SVR2 source distribution, it is
evident that the Bell Labs guys preferred abbreviations to acronyms.
The distributed root filesystem consisted of:

  bck bin etc dev lib stand tmp

The /usr filesystem contained (in cpio format!):

  adm bin catman games include lib lost+found mail news preserve
  pub spool tmp

Not until the top level of the source tape do we hit an acronym:

  cmd games head lib stand uts

where uts="Unix Time-sharing System", which I guess is hard to abbreviate;)

Yes, I know this is somewhat off-topic, but I think it's fascinating,
like, "Why'd they call it 'awk'?"  Now there's an acronym for you.

Today, hier(7) rules.

-- 
Barry

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