+#if defined(__LITTLE_ENDIAN__)
+#define FIO_LITTLE_ENDIAN
+#elif defined(__BIG_ENDIAN__)
+#define FIO_BIG_ENDIAN
+#else
+#error "Undefined byte order"
+#endif
+
+#define fio_swap16(x) OSSwapInt16(x)
+#define fio_swap32(x) OSSwapInt32(x)
+#define fio_swap64(x) OSSwapInt64(x)
+