Find Warning..

[Sjoerd Mullender]

Tom Broadhurst wrote:
>>-----Original Message-----
>>From: fedora-list-bounces at redhat.com 
>>[mailto:fedora-list-bounces at redhat.com] On Behalf Of Nifty Hat Mitch
>>Sent: Saturday, June 18, 2005 6:03 PM
>>To: akonstam at trinity.edu; For users of Fedora Core releases
>>Subject: Re: Find Warning..
>>
>>
>>On Wed, Jun 15, 2005 at 04:41:06PM -0500, akonstam at trinity.edu wrote:
>>
>>>On Wed, Jun 15, 2005 at 04:39:30PM +0200, Jos? Javier 
>>
>>Cuadrado wrote:
>>
>>>>Hello i just did a fresh install of FC4 and when i do a 
>>
>>find i get the following warning. Any tips to fix it? 
>>
>>>>Thanks in advance
>>>>
>>>>find / -name <whatever> 
>>>>find: WARNING: Hard link count is wrong for /proc: this 
>>
>>may be a bug in your filesystem driver. Automatically turning 
>>on find's -noleaf option. Earlier results may have failed to 
>>include directories that should have been searched.
>>
>>>>-- 
>>>
>>>Running find on /proc is bound to cause problems. /proc is 
>>
>>not a real
>>
>>>filesystem it is simulated filesystem created by the kernel to hold
>>>various characteristics of your system.
>>
>>This does seem to be a harmless bug in the /proc filesystem.
>>
>>When I first saw this I dismissed it as the fast moving nature of 
>>the /proc filesystem.  Find can often toss out errors because 
>>what it found and
>>what it 'sees'  (stat etc.) might not match or even still be 
>>a moment later.
>>
>>
>>
>>find: WARNING: Hard link count is wrong for /proc: this may 
>>be a bug in your filesystem driver.  Automatically turning on 
>>find's -noleaf option.  Earlier results may have failed to 
>>include directories that should have been searched.
>>/proc
>>/proc/bluetooth
>>
>>But Looking a little bit closer...
>># ls -lid /proc
>>1 dr-xr-xr-x  140 root root 0 Jun 17 22:07 /proc
>># ls -ali /proc | wc
>>    164    1636   11843
>>
>>So this is why find is tellig us that something is wrong.
>>There are 24 some 'things' that do not have an inode linked to
>>/proc itself.
>>
>>It is a pseudo filesystem intended to communicate to the user
>>various kernel and process info.   It should have all the
>>correctness of any filesystem so I suspect a real bug.
>>
>>As best I can tell this is harmless.
>>
>>
>>-- 
>>	T o m  M i t c h e l l 
>>	Found me a new place to hang my hat :-)
>>	Found me a cable too.
>>
>>-- 
>>fedora-list mailing list
>>fedora-list at redhat.com
>>To unsubscribe: http://www.redhat.com/mailman/listinfo/fedora-list
>>
>>
> 
> Tom
> 
> Excellent detective work.
> This may be harmless, but, as you mention, it's still probably a bug.
> At the least your explanation will allow me to sleep better.
> Thanks again for confirming the problem.

It *is* harmless: this happens when a process dies or starts while find
is searching /proc.  It was very easy to reproduce:

# sleep 1 &
# find /proc -name x
find: WARNING: Hard link count is wrong for /proc: this may be a bug in
your filesystem driver.  Automatically turning on find's -noleaf option.
 Earlier results may have failed to include directories that should have
been searched.

Just take a look at /proc and you'll see that there is a subdirectory
for each process, so that if a process dies, a subdirectory disappears
(and the hard link count on /proc goes down), and when a process starts,
a new subdirectory is created (and the hardlink count on /proc goes up).

-- 
Sjoerd Mullender <sjoerd at acm.org>
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