Creating hardlinks for directories.

[Vikram Goyal]

On Mon, Jan 16, 2006 at 01:03:02PM +0000, James Wilkinson wrote:
> 
> Please note that the ln command and associated manpage come from the GNU
> project. As such, they are certainly not Linux-specific. I understand
> that many of the GNU utilities pre-date the Linux kernel: they were
> certainly designed to install on a large number of weird and
> less-than-wonderful archaic systems. (And this was common, especially
> on systems which saw a lot of interactive shell use).
> 
> So the "possible way of usage" could include "using GNU ln on a
> different system with a different C library and a different kernel".
> 

That's what got me confused in the begning.

> To the best of my knowledge, this *is* the only way. The e-mail at
> http://lwn.net/Articles/100184/ dates from August 2004, but Linus
> Torvalds explicitly says:
>     The general VFS layer has a lot of rules, and avoids these problems by
>     simply never having aliases between two directories. If the same directory
>     shows up multiple times (which can happen with bind mounts), they have the
>     exact same dentry for the directory, it's just found through two different
>     vfsmount instances. That's why vfsmounts exist - they allow the same name
>     cache entry to show up in different places at the same time.
> 
> In other words, if a directory is hard linked, it's a kernel bug.
> 
> James.

I got it. I think I have a workaround yet. Let's see.

Regards!
-- 
vikram...
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