Nikita Danilov wrote:
>
> Hans Reiser writes:
> > A file change notification API is an inherently reasonable thing to have,
> for use by more than just
> > NFS (emacs for instance).
>
> What's wrong with fcntl( F_NOTIFY )?
> I mean, there is standard notification API (and several non-standard
> ones, stolen from BSD) in Linux.
>
> >
> > Hans
>
> Nikita.
>
> >
> > Xuan Baldauf wrote:
> > >
> > > Ragnar KjЬrstad wrote:
> > >
> > > > > > For each open file you have:
> > > > > >
> > > > > > struct file (96b)
>
> Nikita.
It might be perfect for NFS. My man page for fcntl doesn't list F_NOTIFY. I
will guess at what it
does though (yah, I know, I should read the source, but it is late), and say
that it or something
resembling it should be used by NFS. Generation numbers have the feel of a
hack, to my mind. I
would probably feel better about generation numbers if they didn't take up
space in the stat data,
but they would still feel like a hack.
So, do I understand right that Xuan's solution could eliminate the need to
store the generation
number in the stat data? The problem with Xuan's solution though, is that it
is easier to randomly
obtain identical generation numbers for differing versions of the same file.
Am I right?
Maybe in V4 we can make the attribute holding generation numbers be dynamically
allocated. That
way, NFS doesn't burden other FS uses. I bet we won't have time for that extra
touch of programming
before we ship code though. Sigh.
Hans
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