Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!uunet!husc6!bloom-beacon!thor!tytso
From: tytso@thor.mit.edu (Theodore Y. Ts'o)
Newsgroups: comp.unix.wizards
Subject: Re: Symbolic Links
Message-ID: <1362@bloom-beacon.MIT.EDU>
Date: Wed, 31-Dec-69 18:59:59 EDT
Article-I.D.: bloom-be.1362
Posted: Wed Dec 31 18:59:59 1969
Date-Received: Wed, 26-Aug-87 01:27:17 EDT
References: <8731@brl-adm.ARPA> <2789@ulysses.homer.nj.att.com> <1781@munnari.oz> <2838@ulysses.homer.nj.att.com> <1793@munnari.oz> <2854@ulysses.homer.nj.att.com>
Sender: daemon@bloom-beacon.MIT.EDU
Reply-To: tytso@thor.UUCP (Theodore Y. Ts'o)
Organization: Massachusetts Institute of Technology
Lines: 38

In article <2854@ulysses.homer.nj.att.com> ekrell@hector (Eduardo Krell) writes:
>This argument, that ".." is a physical link (rather than a logical one)
>falls appart at mount points, where the parent directory and where ".." points
>are different. It also happens at remote file system mount points, for
>the same reason. So it's not so "simple and consistent". It now requires
>some education about file systems, mount points, and distributed file
>systems. The list seems to keep growing.
>
Yes, Unix requires some education.  I like to think that is a consequence
of its power.  If you want a system that is easy to learn, use a system
with all the flexibility (and "user friendliness") of a Macintosh.
>
>An implementation is not only possible, it already exists. I wouldn't be
>defending this if I didn't have the opportunity to use it and test it and
>get the feeling as to whether it's the right thing to do or not.
>    
Part of the Unix way is to be as flexible as possible.  I HOPE this is 
optional (turned on with a system call, or some such), or are you,
as a religious fanatic, going to force your way on everyone?  Make
it optional, and those who like it off can turn it off, preferably
without needing the source license.  (Or the other solution: using BSD :-)
The above paragraph assumes that someone at ATT is pushing this
interpretation into SYS V.  (Why is it that mostly ATT posters think
this is a good idea?)  If you're discribing a purely local hack, then
I hope it stays that way.

I really think adding state into the .. is really a *bad* idea.  (or could
you guess :-)  It confuses the issue, and it isn't as simple as you
seem to make it out to be.  Example: /mnt/paris is a link to /.
When you boot up in single user mode, before any history is established,
WHERE DOES .. POINT TO?  Since you don't think .. is a physical
pointer, the answer '/' is going to require a lot of explaning.  And
if the kernal flips a coin, I'll let you explain to the user why he
typed cd .. from / and ended up in /mnt.
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Theodore Ts'o				mit-eddie!mit-athena!tytso
3 Ames St., Cambridge, MA 02139		tytso@athena.mit.edu
			If it's for real, it isn't!