Shouldn't GNU tar be ignoring /proc with --one-file-system?

[Terrence Koeman]

> -----Original Message-----
> From: owner-freebsd-questions at freebsd.org [mailto:owner-freebsd-
> questions at freebsd.org] On Behalf Of Daniel Staal
> Sent: Friday, November 18, 2011 18:00
> To: freebsd-questions at freebsd.org
> Subject: Re: Shouldn't GNU tar be ignoring /proc with --one-file-
> system?
> 
> 
> On Fri, November 18, 2011 10:34 am, Kirk Strauser wrote:
> > I use Amanda to make nightly backups of a bunch of servers using GNU
> tar.
> > However, gtar doesn't seem to respect its --one-file-system flag with
> > /proc. Amanda runs a variation of this command:
> >
> >     # /usr/local/bin/gtar --create --file - --directory /
> > --one-file-system --sparse --ignore-failed-read --totals . >
> /dev/null
> >     /usr/local/bin/gtar: ./proc: file changed as we read it
> >
> > Before I file a bug report, can anyone think of a legitimate reason
> why
> > gtar would be touching /proc at all?
> 
> Just a guess, really but:
> 
> /proc is a file on /.  /proc/* are files on /proc.  The former is still
> on
> the root filesystem (if only as a directory stub to be used as a
> mountpoint), so reading it isn't leaving that filesystem.  Reading
> anything *in* it would be.
> 
> Just a thought.
> 

However, the file /proc on fs / should not be changing since a filesystem /proc is mounted over it. The message "./proc: file changed as we read it" indicates whatever /proc it is trying to read did change...

-- 
Regards,
T. Koeman, MTh/BSc/BPsy; Technical Monk

MediaMonks B.V. (www.mediamonks.com)
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