Oron Peled wrote:
On יום שלישי, 19 ביולי 2016 15:23:25 IDT Matthew Miller wrote:
> ...
> I remember when this came up before but can't find it now. I think it
> was changed to 99 when UIDs went to 32 bit and it suddenly started
> being 65535 on some systems and 4294967295 on others. * I was trying to
> figure out why 99 was eventually chosen, but can't find it now.
I believe the uid 99 come from trying not to overlap regular users.
Back then (end of 90's), regular users uid's were:
* On old RedHat Linux >= 500
* On some other Linux systems >= 1000
* On many legacy Unices >= 100 (except on Irix >= 1000)
It was very common to have NFS mounted /home across all servers (with different *NIX
vendors/versions).
So '99' was the "last" uid that was assured not to collide with
uid's of regular users on NFS.
Solaris and IRIX used to have 60001 as nobody, *and* either -2 or 65534
as nobody, either under the same name (!!!) or some alternative similar
to nfsnobody.
I don't think you want to assume that code thinks the two users are
really identical in practice or that it's safe to merge them, though.
-- Steve
--
Steven Bonneville <sbonnevi(a)redhat.com>
Technical Curriculum Architect
Red Hat | Red Hat Training Phone: +1-612-638-0507
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