bin/43871: /usr/tests/util/df/t_df fails with existing local mount

[njoly%pasteur.fr@localhost]

>Number:         43871
>Category:       bin
>Synopsis:       /usr/tests/util/df/t_df fails with existing local mount
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Sep 12 11:55:00 +0000 2010
>Originator:     Nicolas Joly
>Release:        NetBSD 5.99.39
>Organization:
Institut Pasteur
>Environment:
System: NetBSD petaure.lan 5.99.39 NetBSD 5.99.39 (PETAURE) #19: Sat Sep 11 
23:39:15 CEST 2010 
njoly%petaure.lan@localhost:/local/src/NetBSD/obj.amd64/sys/arch/amd64/compile/PETAURE
 amd64
Architecture: x86_64
Machine: amd64
>Description:
df(1) tests fail when local machine has a an mounted partition that match
a tested case, the local values will be checked instead of test ones.
Unmounting the local partition make it succeed.

njoly@petaure [/tmp]> mount | grep /mount/windows/C
/dev/wd0e on /mount/windows/C type ntfs (read-only, local)
njoly@petaure [/tmp]> /usr/tests/util/df/t_df hflag
Executing command [ /bin/sh -c BLOCKSIZE=1k /usr/tests/util/df/h_df -h ]
Fail: stdout does not match golden output
--- expout      2010-09-12 13:41:43.000000000 +0200
+++ /tmp/check.07849a/stdout    2010-09-12 13:41:43.000000000 +0200
@@ -42,4 +42,4 @@
 /dev/ld0g         1.2T       1.2T      -125G 111% /anon-root
 /dev/ld0g         1.2T       1.2T      -187G 117% /anon-root
 /dev/strpct        20T        10T        10T  50% /strpct
-/dev/wd0e          10G       2.7G       7.3G  27% /mount/windows/C
+/dev/wd0e          20G        17G       3.2G  84% /mount/windows/C
failed: atf-check failed; see the output of the test for details

njoly@petaure [/tmp]> sudo umount /mount/windows/C
njoly@petaure [/tmp]> mount | grep /mount/windows/C
njoly@petaure [/tmp]> /usr/tests/util/df/t_df hflag
Executing command [ /bin/sh -c BLOCKSIZE=1k /usr/tests/util/df/h_df -h ]
passed

>How-To-Repeat:
Run df(1) tests on a machine that has a mounted partition maching a case
path.
>Fix: