+
+/*
+ * You'll laugh when I tell you this ... Astonishingly, it turns out
+ * that ActivePerl (which is widely used on Windows) has, in the
+ * header file Perl\lib\CORE\XSUB.h, the following heinous crime:
+ * # define open PerlLIO_open
+ * This of course screws up the use of the "open" member of the
+ * Z_IdAuthentication structure below, so we have to undo this
+ * brain-damage.
+ */
+#ifdef open
+#undef open
+#endif
+
+