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SubjectRe: High UID support for Linux
On Thu, Nov 19, 1998 at 05:38:39PM -0500, Jon Leonard wrote:

> Has anybody looked seriously at supporting 32 bit UIDs on Linux? We'd
> really like to make Linux a commodity at Umich, but with a user base of
> about 100,000, high UIDs are an absolute requirement. I've only just
> started looking at this, but scanning the include files, it would appear
> that some platforms already support high UIDs, but not i386.

Many (most?) people still have libc5 -- which will break.

> Just for grins, I tried changing the typedef in linux/types.h and
> recompiling the kernel. Wouldn't even boot. Then I noticed that the
> uid and gid fields in ext2 inodes are 16 bits. So it seems like this is
> a project, not than a hack. (This was on 2.0.35.)

ext2fs has reserved space for larger uid's -- hurd I beleive uses

> There's enough interest in this on campus that we can throw some
> resources at it. If no one else has this one, we could probably do it.
> If someone is doing it, how do I get in touch? Comments? Advice

We need everyone to move to glibc2 first -- then it shouldn't be so
much of a problem. I'm not sure how we'll make backwards
compatability work though... perhaps reserve uid_t 0 -> 0xffff for
backwards compatability and have a personality flag which in
inherited. This way we can still have libc5 guake and stuff working
via a small wrapper.


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