Subject: kern/202: create in union filesystem writes-through to lower fs
To: None <gnats-admin>
From: Bob Kemp <rsk@ecs.soton.ac.uk>
List: netbsd-bugs
Date: 04/06/1994 05:50:08
>Number: 202
>Category: kern
>Synopsis: create in union filesystem writes-through to lower fs
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: gnats-admin (Kernel Bug People)
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Wed Apr 6 05:50:08 1994
>Originator: Bob Kemp
>Organization:
ECS Dept, Southampton University, UK
>Release: -current 05Mar94
>Environment:
System: NetBSD allegory 0.9a ALLEGORY#0 i386
>Description:
The man page says that creates in a union filesystem only
affect the mounted filesystem. When the create is in a
subdirectory, it is erroneously done in the underlying
filesystem.
Perhaps this is more an error in the phrasing of the manual page.
[ I expected something (a little) like Sun's TFS and I can't now
see many applications for this simpler union filesystem. Ho hum,
the rest of the system is great anyway (:-) ]
>How-To-Repeat:
Script started on Mon Apr 4 19:45:22 1994
# mount -o union /dev/vnd0c /usr
# cd /usr
# ls
SOFT-ERROR bin/ libexec/ obj/ share/
X386/ include/ local/ ports/ src/
allegory@ lib/ mdec/ sbin/
# df . hosts bin/hosts
Filesystem 1K-blocks Used Avail Capacity Mounted on
/dev/vnd0c 1283 0 1218 0% /usr
df: hosts: No such file or directory
df: bin/hosts: No such file or directory
# cp /etc/hosts .
# df . hosts bin/hosts
Filesystem 1K-blocks Used Avail Capacity Mounted on
/dev/vnd0c 1283 2 1216 0% /usr
/dev/vnd0c 1283 2 1216 0% /usr
df: bin/hosts: No such file or directory
#
# cp hosts bin/hosts
# df . hosts bin/hosts
Filesystem 1K-blocks Used Avail Capacity Mounted on
/dev/vnd0c 1283 2 1216 0% /usr
/dev/vnd0c 1283 2 1216 0% /usr
/dev/wd0f 76403 69246 4864 93% /usr
# df bin/hosts
Filesystem 1K-blocks Used Avail Capacity Mounted on
/dev/wd0f 76403 69246 4864 93% /usr
# cd /
# umount /usr
# cd /usr
# df bin/hosts
Filesystem 1K-blocks Used Avail Capacity Mounted on
/dev/wd0f 76403 69246 4864 93% /usr
# rm bin/hosts
# ls
SOFT-ERROR bin/ libexec/ obj/ share/
X386/ include/ local/ ports/ src/
allegory@ lib/ mdec/ sbin/
#
# exit
Script done on Mon Apr 4 19:48:06 1994
>Fix:
>Audit-Trail:
>Unformatted:
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