Arla 0.42-RC2

[Niels Möller]

Tomas Olsson <tol at stacken.kth.se> writes:

> > But I don't feel I'm the right person to argue about that with the
> > glibc folks. Either someone else has to do that, or arla needs some
> > workaround for the problem.
> > 
> Any ideas?

There are three possible ways, as far as I can see:

1. Copy needed files (libgcc_s.so*, maybe /etc/ld.so.*) into the
   change root. I know postfix copies /etc/resolv.conf into its
   changeroot, for similar reasons. Don't know what naming conventions
   arlad use for cache files, but I guess it should be easy to ensure
   that there are no naming collisions.

2. Link explicitly with the needed file. That's what I do now, I added
   -lgcc_s on the linker command line. Or use LD_PRELOAD for the same
   effect, but I'm not very familiar with that feature.

3. At run time, force loading of the needed library before the chroot.
   As far as I can see, starting and exiting a dummy thread should be
   sufficient.

The last alternative at least has the advantage that it doesn't need
any configuration, it should work on all platforms, do noithing, and
just work as a sanity check of the pthreads implementation.

> I doubt that one can argue from a standards standpoint, SUS2 says[1] about
> chroot() "There is no portable use that an application could make of this
> interface." 

Ooops.

Regards,
/Niels