> Agreed. Now, here's a bit that I still don't quite > understand: Plan9 does have DMAPPEND on > a per-Qid basis. Why was it decided not to > have it on a per-Fid basis (which would match > POSIX semantics 100%)? > > The way I understand -- DMAPPEND is just a hint > to the server to *alway* ignore the offset in > incoming writes. It seems that ignoring offsets > in writes for the Fids that asked for it wouldn't be > much more difficult, would it?
DMAPPEND, for servers that implement it, is not a hint to the server, it's a write to the end of the file, whatever offset that might be. since the end is computed on the file server, multiple concurrent writers don't cause a problem. since the fs is in a position to serialize appends to the same file. - erik
