2 Aug
2019
2 Aug
'19
1:18 p.m.
arnold(a)skeeve.com <arnold(a)skeeve.com> wrote:
BSD again :-) SCCS revision 6.6 so I think it appeared in 4.3BSD
https://svnweb.freebsd.org/csrg/sys/ufs/ffs/ufs_lookup.c?r1=15809&r2=16…
Tony.
--
f.anthony.n.finch <dot(a)dotat.at> http://dotat.at/
Mull of Galloway to Mull of Kintyre including the Firth of Clyde and North
Channel: Variable 1 to 3, becoming easterly or southeasterly 2 to 4 later.
Smooth, occasionally slight at first in North Channel. Showers for a time near
shore. Good.
Arthur Krewat <krewat(a)kilonet.net>:
When Bill Joy added the "multi-group stuff" to BSD all directories became
implicitly set-gid:
https://svnweb.freebsd.org/csrg/sys/ufs/ffs/ffs_inode.c?r1=4818&r2=5855
This is in SCCS revision 4.8 so I think it appeared in 4.2BSD
As I understand it, when group support was improved in System V they did
not change creat() to match BSD but instead used the directory set-gid bit
to provide opt-in BSD semantics. I don't know if this was in Solaris or
earlier?
There's also the setgid bit on directories,
that when files are created,
they will be in the group that the parent directory has on it.
IIRC this was a Sun invention. It was in SunOS 4.x, and may even have
been in SunOS 3.x. Also, I
don't think it's been mentioned, but there's the setuid bit on
directories - otherwise known as the sticky bit. When set, even if you
have rights to "write" the directory (meaning, delete files), you can't
delete those owned by other users. Useful for /tmp
Also a SunOS invention, IIRC.