+#if defined(__VISAGECPP__)
+typedef uLong (ZEXPORT _Optlink *check_func) OF((uLong check, const Bytef *buf,
+ uInt len));
+voidpf _Optlink zcalloc OF((voidpf opaque, unsigned items, unsigned size));
+void _Optlink zcfree OF((voidpf opaque, voidpf ptr));
+#else