From mboxrd@z Thu Jan 1 00:00:00 1970 From: tuhs@cuzuco.com (Brian S Walden) Date: Thu, 9 Jan 2014 16:29:11 -0500 (EST) Subject: [TUHS] History of chown semantics Message-ID: <201401092129.s09LTBBg001272@cuzuco.com> it follows the philosophy of pwb -- a usable system for disparate small groups of developers on the same hardware that could be managed by admins not system programmers. read http://www3.alcatel-lucent.com/bstj/vol57-1978/articles/bstj57-6-2177.pdf for the flavor of that time, and you'll understand better. > From: Clem Cole > > Brian - right as I showed in the code snippet from V6 and PWB. The idea > came into being with PWB. > The question that is still open is why was it added/need in the first > place? I always thought is was a crazy/miss feature, > > I think the argument is that if you owned the file, you should be allowed > to give it to anyone else [including root] - but that actions opens up a > number of issues (you pointed the big security one that was handled by > and-ing off the SUID/SGID bits). There are accounting issues as well as > the practical one that Tim and I pointed out with importing of files on a > tape. > > As I said, the file give-away feature comes into UNIX with PWB, so I would > ask Mash is he remembers why it was needed and why the SVID folks wanted > it. As I said, I personally found it not useful/a bad idea/miss-feature. > I remember that I soon after I learned about it/got bitten by the side > effect, I ran into dmr and srb at a USENIX and asked them about that a few > other System III features that I found a little strange. I don't remember > much of the conversation. But, if there are been a "good" reason I think > I would have remembered it and not always thought it to be a bad idea. > > Clem