CGMainDisplayID() doesn't exist on 10.1, so don't try to call it when
building for that platform.
diff --git a/Mac/Modules/macosmodule.c b/Mac/Modules/macosmodule.c
index 271a5aa..298aa0c 100644
--- a/Mac/Modules/macosmodule.c
+++ b/Mac/Modules/macosmodule.c
@@ -439,9 +439,16 @@
** It appears the function caches the result itself, and it's cheap, so
** no need for us to cache.
*/
+#ifdef kCGNullDirectDisplay
+ /* On 10.1 CGMainDisplayID() isn't available, and
+ ** kCGNullDirectDisplay isn't defined.
+ */
if (CGMainDisplayID() == 0) {
rv = Py_False;
} else {
+#else
+ {
+#endif
if (GetCurrentProcess(&psn) < 0 ||
SetFrontProcess(&psn) < 0) {
rv = Py_False;