patch draft for extended attributes on linux
jw at pegasys.ws
Wed Jun 25 10:56:22 EST 2003
On Wed, Jun 25, 2003 at 10:34:38AM +1000, Martin Pool wrote:
> This draft patch adds support for transferring extended attributes
> with a new --xattr option. It ought to work on Linux with XFS or
> ext2/ext3 filesystems with the SGI/bestbits attribute system.
> It is partially working, but there seems to be some kind of hang bug
> while transferring the file list. I suspect it might be provoking a
> problem in io.c.
> You need to rerun autoconf, autoheader and configure after applying
> There is no mtime for xattrs, so they are transferred every time as
> part of the file list. This means that they will be updated correctly
> if you change attributes but do not change the file.
That lack of an mtime for xattr could well cause
difficulties for backup systems as well. Perhaps a note to
the filesystems people is in order. The problem is that you
can't use mtime for these. It really needs its own
timestamp, perhaps as a mandatory system attribute.
I don't much care for
sending the xattrs as part of the file list. Even the 4KB
ext _currently_ limit it to is huge.
> I wrote this because it was required by a colleague. I have mixed
> feelings about whether this ought to be merged, even once it's working
> correctly. rsync hardly needs more options or protocol
> variations. :-( (Amusingly enough I once said "-xattr" instead of
> "--xattr" and it silently did something else.)
I don't have a problem with the idea of adding such an
option and protocol variant to rsync. Doing it this way i
do have more than mixed feelings about merger. My feelings
on this are already well articulated in the archives.
Nevertheless i do think it worth having something in
patches. I have a vague recollection of an earlier patch
that did an lsattr and synced that before applying it,
perhaps something in that vein might be more apropos.
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