Re: Recent changes to sysctl.h breaks glibc

[ebiederm@xmission.com (Eric W. Biederman)]

"H. Peter Anvin" <hpa@zytor.com> writes:

> Followup to:  <Pine.LNX.4.44.0305191039320.16596-100000@home.transmeta.com>
> By author:    Linus Torvalds <torvalds@transmeta.com>
> In newsgroup: linux.dev.kernel
> > 
> > A number of headers have historical baggage, mainly to support the 
> > old libc5 habits, and because removing the ifdef's is something that 
> > nobody has felt was worth the pain.
> > 
> > I think the only header file that should be considered truly exported is 
> > something like "asm/posix_types.h". For the others, we'll add __KERNEL__ 
> > protection on demand if the glibc guys can give good arguments that it 
> > helps them do the "copy-and-cleanup" phase.
> > 
> 
> Copy and cleanup isn't realistic either, though, because it doesn't
> track ABI changes.  

ABI changes or ABI additions?

If the ABI is not fixed that is a bug.  Admittedly some interfaces
in the development kernel are still under development and so have not
stabilized on an ABI but that is a different issue.

> ABI headers is the only realistic solution.  We
> can't realistically get real ABI headers for 2.5, so please don't just
> break things randomly until then.

As the ABI remains fixed I remain unconvinced.  Multiple implementations
against the same ABI should be possible.  The real question which is the
more scalable way to do the code.

What I find truly puzzling is that after years glibc still needs
kernel headers at all.

Eric