From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <006501c15261$226a9440$8e8b0241@sumt1.nj.home.com> From: "david presotto" To: <9fans@cse.psu.edu> References: <20011010130436.D697919A3E@mail.cse.psu.edu> <87sncr7y7g.fsf@becket.becket.net> Subject: Re: [9fans] correcting old failures, and NJ vs MA MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Date: Thu, 11 Oct 2001 10:29:27 -0400 Topicbox-Message-UUID: 0676f6d2-eaca-11e9-9e20-41e7f4b1d025 > presotto@closedmind.org writes: > > > Moving a directory doesn't fall into any of these categories, though > > some parts of the operation do. The move itself should be in a library > > if it's going to be used by more than one program. > > Moving a directory can *NOT* be done in constant time without special > kernel support. Even a Version 7 style unlink/link if it allowed > links to directories would at least allow it to be possible (though > with additional race conditions). Plan 9 directory moves can't be done in constant time since, at the very least, the name space has to first be walked to see if it can be done quickly. The only way to do it would be to change how mounting works in the kernel, perhaps adopting something like Sprite's prefix matches. That would change the system to be something very different than it currently is, just to get a constant time directory move. Perhaps a worthwhile experiment, in fact one I'ld like to do sometime for different reasons, but the result would be a very different system. I said that there were some parts of the operation that should be done in the kernel. Doing the whole thing in the kernel is sub optimal, mostly because handling all the edge conditions would involve doing file copies, etc, things that are easier to clean up after failure at user level.. Were you just violently agreeing with me or is this some sort of psychology experiment? > > As for find, this isn't rocket science. Quit yapping and implement it > > if you want it. > > Alas, while I'm interested in the design and ideas of Plan 9, I'm not > interested in contributing to someone's commercial (non-free-software) > project unless I get remunerated. > > Thomas Your loss though you weren't the only one asking for find. I'm happy just composing du -a, grep, sed, and `{}.