On Sat, Sep 07, 2002 at 07:23:10PM +0100, David Laight wrote:
> > >Synopsis:       patch to allow a uid or gid of (-2) matching default
> >		   NFS mapping for remote root users
> > 
> > 	increase UID_MAX and GID_MAX to (UINT_MAX-1)
> 
> Wouldn't it be better to use (~(uid_t)0 - 1) and (~(gid_t)0 - 1) ?

A quick look at the history of syslimits.h (brought on by the fact
that the comments for these values didn't match the value) shows
that the limit has been 2^32-2 before.

It was changed because setreu/gid() allows -1 (meaning don't
change) which has to be within the domain of u/gid_t.

This is another of those types [1] whose domain is -1..MAXINT-1
that C doesn't quite copy with.

	David

[1] includes pid_t and the return value from lseek(), probably
really size_t in genaral.

-- 
David Laight: david@l8s.co.uk