This is supposed to be a generic and expandable mechanism. NFS/DFS referrals are just primary consumers of this mechanism at this point so this is not a protocol specific mechanism to have a per protocol extended attribute that are hard coded before hand.
If we want to use extended attributes then we either have to reserve some namespace or use an extended attribute with a reserved name as an index. It also makes path name reduction very expensive because for each component we have to do a lot of extra stuff to see whether we are dealing with a reparse point or not and whether that reparse point contains the data that we are interested in. I also think symlink does not quite support extended attributes. Afshin Nicolas Williams wrote: > On Fri, Jul 10, 2009 at 09:34:26AM -0700, Glenn Skinner wrote: >> The reparse data will be stored as the link target. The >> reparse data is not in file system path format, which is the >> typical format of a link target. In order to avoid coming up >> with a totaly new format for reparse data as the link target >> we decided to adopt the format used by magic links in BSD: >> (http://www.daemon-systems.org/man/symlink.7.html) >> >> @{repa...@{service-type1:data} [...@{service-type2:data}]...} > > I see no UI/CLI/API for managing this. Exposing users to this format > seems most unfriendly. > > I think a CLI should be provided if such a complex format is to be used > to store the referral data. It could be a simple script for all I care. > > Also, how about storing referral data in a per-protocol extended > attribute instead of all of it as symlink contents? That would be much > cleaner since then: > > - the type of the object (symlink, dir, file...) becomes irrelevant > - one can export that object for some protocols, a referral for others > - that object could be a symlink with a /net path -- a very nice > fallback for NFSv3 > > Does using EAs cause problems with backup tools? If so, is that really > a big deal? Wouldn't backup tools that can't backup EAs be problematic > anyways? > > Nico
