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From: csg@pyramid.pyramid.com (Carl S. Gutekunst)
Newsgroups: comp.sys.sequent
Subject: Re: mv not atomic in dynix
Keywords: mv
Message-ID: <145463@pyramid.pyramid.com>
Date: 19 Feb 91 23:55:23 GMT
References: <1991Feb16.000101.4149@ux1.cso.uiuc.edu>
Organization: Pyramid Technology Corp., Mountain View, CA
Lines: 17

If you are talking about DYNIX (4.2BSD), this is not true; the rename(2)
system call is used and it is atomic. Assuming you aren't using the mv(1) in
the att universe, of course.

If you are talking about DYNIX/ptx (SVR3.2), then you are correct. There is
no rename(2) call, mv(1) is not atomic (it uses link(2) and unlink(2)), and
you are SOL. That's just the way System V works.

[Editorial Comment: Companies that give the same name (or a trivial variation,
like the version code) to radically different operating systems should be
lynched by their justifiably outraged customers. That includes the old Gould,
which had who-knows-how-many different things all called UTX; Sun, which last
I knew is going to call their SVR4 port "SunOS 5.0"; and many others. Sequent
chose to walk a very well trodden path, and I know of other companies that
plan to follow.]

<csg>