exec* vs. initially-closed file descriptors in a set-ID context

[Jim Meyering]

Ulrich Drepper <drepper@redhat.com> wrote:
> I've changed the code to use the proposed modes.  There is one
> additional step in the new code: for the writable descriptor 0 we're now
> using /dev/full which causes the operation to fail even if 0 is
> invalidly is used for writing.

Thanks for the quick fix.
I like the idea of using /dev/full for descriptor 0.

This seems to be the first use of /dev/full in glibc.
Do all of glibc's target systems provide a usable /dev/full?