Implementing file-attributes with "stat"?

[Kai Großjohann]

Tramp now uses a Perl implementation of file-attributes, if Perl is
available on the remote host.  But I get the feeling it might be nice
to use the "stat" program, if available.  But I know nothing about
it.  Does somebody know if stat can be used in a portable way such
that it returns the data we need?

(Type C-h f file-attributes RET for information on the data that's
needed.  Some of it, such as the device number, can be faked without
too much trouble.)

I would be happy if you could do the Lisp part, but if you don't want
to do that, it's also fine.  What I need is information on the
command line to use to invoke stat, and how to parse the result.  I
typed "stat /" but the result was not *that* enlightening.  Hm.
Though, with some pondering, I could probably figure it out.

How portable is stat?  Does it behave similarly on all systems where
it is available, or are there very different implementations?
(Cf. uuencode and uudecode; there are many implementations out that
that differ quite a bit.)
-- 
Two cafe au lait please, but without milk.