-                       int SerialStream_TxByte(char DataByte, FILE *Stream) ATTR_NON_NULL_PTR_ARG(2);\r
-                       int SerialStream_RxByte(FILE *Stream) ATTR_NON_NULL_PTR_ARG(1);\r
+               #if defined(INCLUDE_FROM_SERIALSTREAM_C)\r
+                       static int SerialStream_TxByte(char DataByte, FILE *Stream) ATTR_NON_NULL_PTR_ARG(2);\r
+                       static int SerialStream_RxByte(FILE *Stream) ATTR_NON_NULL_PTR_ARG(1);\r
+               #endif\r