Re: [TUHS] History of chown semantics

I am also interested in this (and had researched it a little for my book about history of Berkeley Unix). A few years ago, Thompson had told me that while at Berkeley (on a sabbatical), he did a modification at Berkeley to put in disk space quotas to prevent runaways. (This "Berkeley" modification is also mentioned in the pascal docs, see http://minnie.tuhs.org/cgi-bin/utree.pl?file=2BSD/doc/pascal/puman3.n ) I thought it was as a side-effect of this that users couldn't chown files to others (since can't cause quota problems for others). But now I see that already existed: http://minnie.tuhs.org/cgi-bin/utree.pl?file=V6/usr/man/man8/chown.8 from 1975 mentions "Only the super-user is allowed to change the owner of a file, in order to simplify as yet unimplemented accounting procedures." But it appears that some Berkeley systems did have a concept of some non-root users chowning files. Apparently there was a Berkeley Fascist File System where only group masters were able to chown files owned by members of a group. I also read there was a concept of "class users" (uid < 0) who could not access others files regardless of open permissions. For references see http://www.dnull.com/bsd/oldnews/bsdnew20597.html https://groups.google.com/forum/#!original/net.unix-wizards/RasSNg_DNHM/2Ty… https://groups.google.com/forum/#!original/comp.unix.questions/I1nkZGl8Hl0/… (Ed Gould from Berkeley also mentioned it to me.) http://minnie.tuhs.org/cgi-bin/utree.pl?file=2BSD/upgrade/src/last.c mentions "non-class users". http://minnie.tuhs.org/cgi-bin/utree.pl?file=1BSD/man6/dates.6 manual mentions "class master accounts". http://minnie.tuhs.org/cgi-bin/utree.pl?file=1BSD/man6/whoison.6 appears to define "class" and winfo database (which is not in 2BSD). http://minnie.tuhs.org/cgi-bin/utree.pl?file=1BSD/s6/chownall.c has: if (chgusr && !chggrp && source.uid == 0) panic("owner of \"%s\" is uid 0 in his group !?!", spth); else if (!chgusr && chggrp && source.uid != 0) panic("owner of \"%s\" is not uid 0 of his group !?!", spth); http://minnie.tuhs.org/cgi-bin/utree.pl?file=1BSD/man6/chownall.6 also mentions the "user number 0 in his group." I am not sure what this concept of uid 0 "of a group" means. The way it is all worded I don't think it is superuser uid 0. I think "group master" is the same as "class master" and same as "uid 0 of a group". Can anyone explain this? (I can't find this concept in 2BSD nor 3BSD.) Maybe this too much of a tangent, but seems to be about an old example of users giving away files.