On Sun, Jun 13, 2010 at 1:17 PM, Roland McGrath <rol...@frob.com> wrote: >> Is the empty string supposed to refer to the node itself somehow? > > It does. To look up "." you need search (execute) permission on the > directory. To look up "" it just has to actually be a directory port. > At least, that's the way I remember it from the previous millenium.
Okay, thanks, I didn't know that. I've checked fs.defs and the behavior you describe is documented for dir_lookup(). (for what it's worth it says that the null string should be supported on non-directory files too). However there's nothing such for the calls manipulating the links of a directory such as dir_mkdir(), dir_rmdir(), dir_unlink() and so on. These apparently return EINVAL on an empty string (or at least my /hurd/ext2fs does). > (...) >> I'm thinking more and more that it's the libc's job to handle this >> case, rather than passing the ambiguity on to the file system server. > > I don't follow. I mean there's no link to be manipulated here, which is what these RPC calls are about; and you're right that the distinction between links and nodes is important. Considering this I'm not sure we should require them to handle the empty string case. -- Jérémie Koenig <j...@jk.fr.eu.org> http://jk.fr.eu.org/
