Re: Does git belong in root's $PATH?

From: H. Peter Anvin <hpa@zytor.com>
Date: Jan 8, 2006, 03:00 UTC
Message-ID: <43C08047.6090701@zytor.com>
In-Reply-To: <dpppg4$qkd$1@sea.gmane.org>

walt wrote:

Show 9 quoted lines

> H. Peter Anvin wrote:
> 
>>/usr used to be what is now called /home.  What you're describing above
>>is the current usage.
> 
> History lessons are valuable for us youngsters ;o)  Can you give us a
> brief description of what motivated such a change?  (Just as important,
> of course, is whether the original motives have changed or disappeared.)
>

This is the history as far as I understand it. Keep in mind I was only 8 years old in 1980, and I think I first learned about how Unix worked in 1985 or 1986, so not all of this is first-hand.

/usr was initially used for home directories (user directories.) Both fore reasons as have been previously discussed (remember, most easy multi-user systems were a lot friendlier than one would expect today), and because the root disk often filled up, it became common for users to put binaries in /usr/bin, and often the sysadmin, too.

As the need for system security tightened, by the 80's this was a pretty unusable configuration. Since home directories were specified in /etc/passwd, those could, and often were, located elsewhere -- much easier than trying to change the now-established conventions of /usr/bin et al. A lot of systems in the 80's were massively multiuser anyway (workstations were coming in but were rare), and so you'd frequently see paths like /u2/h/hpa for example (my actual home directory location on our college server.)

The convention of using /home for home directories seems to have evolved out of necessity when networking came in use on a large scale (NFS, automounter, etc), probably in the late 80's-early 90's. By the time Linux emerged in 1991 it was pretty well-established on smaller systems; larger systems still tended to use local conventions inherited from previous generation systems.

	-hpa