Subject: Re: Union Filesystem
To: Jason R. Fink <jrf@adresearch.com>
From: Konrad Schroder <perseant@hitl.washington.edu>
List: tech-kern
Date: 11/08/2002 16:58:09
On Fri, 8 Nov 2002, Jason R. Fink wrote:

> Filesystem       1K-blocks     Used     Avail Capacity  Mounted on
> /dev/wd0a          2053695  1278178    672832    65%    /
> /dev/wd0e         31764068  1745591  28430273     5%    /usr
> <above>:/tmp/foo   3799286  3023769    672832    81%    /usr/bar
> deimos# touch /tmp/foo/baz
> deimos# touch /usr/bar/buz
> deimos# ls /tmp/foo
> baz buz
> deimos# ls /usr/bar
> baz buz

Both of those files were created in /tmp/foo, and not in the version of
/usr/bar that is "below" the union mount, though the union of (the hidden)
/usr/bar and /tmp/foo contains both.  If you do

	deimos# umount /usr/bar
	deimos# ls /usr/bar

it should come up empty.

------------------------------------------------------------------------
Konrad Schroder          http://www.hitl.washington.edu/people/perseant/
Information Tech & Services   Box 352142 -or- 215 Fluke Hall, Mason Road
Human Interface Technology Lab                  University of Washington
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