Extattr portability?

[Robert Watson]

On Wed, 7 Jan 2009, Tim Kientzle wrote:

> I'm trying to complete the extended attribute support in libarchive.  There 
> are a handful of odd issues that arise which I think I could resolve if I 
> knew of good use cases.
>
> Anyone here actually use extended attributes?  (Note that ACLs are handled 
> separately.)  What software?  What information do you store there?
>
> If you could benefit from being able to move extended attributes between 
> FreeBSD and other systems, I'm especially interested.

Most (all) of the use of extended attributes that I'm aware of on FreeBSD 
relates to security extensions, be it ACLs, MAC labels (almost always in the 
system namespace) for various policies, etc.  Mac OS X is now using extended 
attributes in quite a few more ways, however, so you may want to investigate a 
bit on that side.  Most uses I'm aware of aren't intended to be portable.

Robert N M Watson
Computer Laboratory
University of Cambridge