Alan Coopersmith authored Sep 21, 2014 and Keith Packard committed Oct 09, 2014

make -j 8 check was sporadically failing in different xi2 tests.
After adding the asserts in the previous commit to catch xkb failure
it became easier to catch the failures and see that multiple tests
were running at once trying to write to /tmp/server-(null).xkm and
then delete it, and interfering with each other.

Putting a unique string into the display variable let them each write
to their own file and not interfere with others.

v2: Fix Linux bits:

  Add #include <errno.h> to get a declaration of
  program_invocation_name on Linux.

  Use only the last portion of the pathname so that the resulting
  display name doesn't contain any slashes.

v3: use program_invocation_short_name on Linux

  This is the same as program_invocation_name, except is has
  stripped off any path prefix.

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>