> >  > Given the way that (the only file handles I've looked at in detail)
> >  > were generated, you would be better picking out the 32 bits that
> >  > are the inode number on the target filesystem.
> > 
> > This doesn't work so well for an NFS client; the file handles are supposed
> > to be opaque to the client.
> 
> But there is no reason why it shouldn't optimise for what it expects to
> see most often....

yes, there is, since some nfs server will some day put all zeros into the
32 bits you're deciding to guess at.  opaqueness isn't debatable here.