RE: Emacs on QNX

[Elad Lahav]

> Hmm, there appears to have been a typo in configure.ac, which I also
> fixed with the attached patch. Why didn't this typo prevent your build
> from working?

We got lucky, due to the following lines in configure.ac:

===
  cygwin | qnxto)
          hybrid_malloc=yes
          system_malloc= ;;
  *) test "$ac_cv_func_sbrk" = yes && system_malloc=$emacs_cv_sanitize_address;;
esac

if test "${system_malloc}" != yes && test "${doug_lea_malloc}" != yes \
   && test "${UNEXEC_OBJ}" = unexelf.o; then
  hybrid_malloc=yes
fi
===

Since 'qnxnto' doesn't match any other case, it goes to the default, and since 
$emacs_cv_sanitize_address happens to be "no" hybrid_malloc still gets defined.

As a side note, porting Emacs finally drove me to implement openat()/fstatat(), 
which have been on the to-do list for a very long time (not as trivial as you 
may think in a micro-kernel environment, where different files within the same 
directory may be provided by different external servers).

--Elad