Re: /proc and other Linuxisms

[Marcus Brinkmann]

On Wed, Feb 13, 2002 at 02:29:36PM -0500, Ludovic Courtès wrote:
> The Hurd glibc should have the same symbols as the Linux' glibc, right?

You will have some interesting hours if you play with objdump and readelf.

We differ in many ways, for example in the versioning.  I can only
reiterate, we are deliberately not ABI compatible now, but might be at some
day.  There are no serious obstackles.

> Then,
> what under the Hurd /lib/ld-linux.so was just a symlink to the Hurd equivalent
> (is it /lib/lib-hurd.so?) or a simple wrapper to the Hurd equivalent
> function calls?

When we are compatible, we will use our linker and stuff.  It will just
work.  (Such a symlink seems to be necessary, yes).
 
> Would it be sufficient to have a "simple" Linux binary (i.e. a program that
> does not used pthreads for instance) running under the Hurd? What would
> happen?

The linker will refuse to load it, because it will notice the different
.note.ABI-tag (that is one of the _first_ reasons it will refuse it.  If you
disable the check, it will fail for other reasons).
 
> Where can we find documentation about how those different layers work
> together (maybe in the Linux doc)?

There is various material.  There are books about loaders and linkers.  But
there is no document I am aware of that covers "how to run binaries from
system GNU/Linux on system GNU/Hurd".  You will have to do your own
research.
 
> > One thing is libio, we will get that now (*sigh* some hard bugs in the way,
> > though, difficult to debug.  It works in a chroot, but not at boot time).
> 
> What is libio?

libio is an implementation of the stdio library.

Thanks,
Marcus

-- 
`Rhubarb is no Egyptian god.' Debian http://www.debian.org brinkmd@debian.org
Marcus Brinkmann              GNU    http://www.gnu.org    marcus@gnu.org
Marcus.Brinkmann@ruhr-uni-bochum.de
http://www.marcus-brinkmann.de