> Date: Wed, 19 Apr 2006 23:45:20 +0200
> From: Roland Mainz <roland.mainz at nrubsig.org>
>
> April Chin wrote:
> > > April Chin wrote:
> > > > > From: Roland Mainz <roland.mainz at nrubsig.org>
> > > > > Joerg Schilling wrote:
> > > > > > Roland Mainz <roland.mainz at nrubsig.org> wrote:
> > > > > > > Markus Gyger wrote:
> > > > > > > > I patched ksh93n+ back then so that cd -@ could be used to
access
> > > > > > > > extended file attributes (instead of having to use runat).
> > > > > > > > Patch
is
> > at
> > > > > > > > http://www.blastwave.org/mantis/show_news?f_project_id=0000027
> > > > > > >
> > > > > > > http://www.blastwave.org/~mgyger/ast.diff.gz is the lastest patch,
> > right
> > > > > > > ?
> > > > > > >
> > > > > > > > (dated, of course).
> > > > > > >
> > > > > > > How common are the XATTR extension, e.g. is there any other OS
which
> > > > > > > supports this feature+userspace API ? Is there any other shell
which
> > > > > > > supports "cd -@" ?
> > > > > >
> > > > > > Currently only Solaris supports it but other OS are underway to
> > implement
> > > > full
> > > > > > NFSv4 support which usually includes XATTR support.
> > > > >
> > > > > Is the XATTR userspace API some kind of standard (UnixXXX or something
> > > > > like that) ?
> > > >
> > > > No, the extended attributes interfaces in Solaris are not specified by
the
> > > > standards.
> > >
> > > Even no drafts or standard proposals (well, I am worrying what the Linux
> > > people may do with the API... ;-( ) ?
> >
> > I asked our standards expert, and there is nothing being proposed for
> > extended attributes, e.g., no specifications for -@ options for
> > utilities. There is a draft of a subset of functionality for
> > *at() interfaces (operations against
> > a path relative to a fd) proposed for *possible* inclusion in the next
> > revision of SUSv3, but again, not dealing with extended attributes.
>
> I think it is important to invite the people (e.g. who (emails!) wrote
> this new API ?) who wrote this API to discuss how the shell should
> handle these special files. The lack of a standard and the fact that
> these files are completely inaccessible from within a shell session is a
> very bad thing and should be addressed before inclusion into SuSv3 is
> done.
>
I understand the API's being proposed for relative path interfaces
were proposed for the purposes of walking arbitrary depth directories
and have nothing to do with extended attributes. Also there is no
guarantee that these API's will make it into SUSv4.
What may make more sense is to bring this to the attention of
those responsible for extended attributes. I can raise the issue
within Sun, if this is useful.
When you say "completely inaccessible", do you really mean that
ksh93 has no *portable* way of directly accessing extended attributes?
The Solaris utilities with extended attributes access
(runat and -@ options to mv, cp, ls, etc.)
may still be executed in ksh93, the same as they are under all the
Solaris shells, which have no special extended attributes code.
If you want to utilize the Solaris interfaces to extended attributes
in ksh93 code directly,
you could embed them within
#ifdef O_XATTR
...
#endif
--April
> ----
>
> Bye,
> Roland
>
> --
> __ . . __
> (o.\ \/ /.o) roland.mainz at nrubsig.org
> \__\/\/__/ MPEG specialist, C&&JAVA&&Sun&&Unix programmer
> /O /==\ O\ TEL +49 641 7950090
> (;O/ \/ \O;)
