rfc: [patch] change attribute for ext3

[J. Bruce Fields]

On Wed, Sep 13, 2006 at 01:31:30PM -0600, Andreas Dilger wrote:
> On Sep 13, 2006  18:42 +0200, Alexandre Ratchov wrote:
> > The patch also adds a new ``st_change_attribute'' field in the stat
> > structure, and modifies the stat(2) syscall accordingly. Currently the
> > change is only visible on i386 and x86_64 archs.
> 
> Is this really necessary for knfsd?

Of course knfsd is completely in kernel, so it doesn't care about the
userspace interface.

But I think that a change attribute is potentially an *extremely* useful
thing, and for more than just nfs servers.  Lots of userspace programs
also need to know whether a file has changed since they last examined
it, and also suffer from the limitations of using ctime or mtime as an
imperfect approximation to a real change attribute.

But it would make sense to split the user space changes into a second
patch and possibly apply it later.

--b.