Subject: bug#14383: cp --one-file-system / will not copy whole root filesystem

From: Pavel Machek <[email-masked]>
Date: Fri, 10 May 2013 19:29:47 +0200

Hi!

> But isn't that the entire purpose of -x?  To avoid copying files on
> other file systems?
> 
> I am just not sure about having a description that is "don't copy
> files on other filesystems" and then "warning: does not copy files on
> other filesystems".
> 
> I have never liked the wording of "stay on this file system".  Usually
> describing things in the positive, saying what it does, is best.  But
> I always felt that with -x describing it in the negative, saying what
> it does not do, would be better wording.

No no, I'm saying that it will not copy data on *this* filesystem;
because other filesystem is mounted over those data.

Lets say you have this on your / (ext3):

/
/dev/foo

But your distro mounts devtmpfs over /dev, so /dev/foo is not visible,
and not copied :-(.

Not that cp can do much about that, but I tried to backup my /
filesystem, and that's exactly what happened.
 
									Pavel
-- 
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