diff --git a/include/nana/filesystem/filesystem_selector.hpp b/include/nana/filesystem/filesystem_selector.hpp
index b0d3ae3a..5a8eac29 100644
--- a/include/nana/filesystem/filesystem_selector.hpp
+++ b/include/nana/filesystem/filesystem_selector.hpp
@@ -29,6 +29,10 @@
 
 #include <nana/config.hpp>
 
+#define NANA_USING_NANA_FILESYSTEM  false
+#define NANA_USING_STD_FILESYSTEM   false
+#define NANA_USING_BOOST_FILESYSTEM false
+
 #if (defined(NANA_FILESYSTEM_FORCE) || ( (defined(STD_FILESYSTEM_NOT_SUPPORTED) && !defined(BOOST_FILESYSTEM_AVAILABLE)) && !(defined(BOOST_FILESYSTEM_FORCE) || defined(STD_FILESYSTEM_FORCE)) ) )
 
 #   include <nana/filesystem/filesystem.hpp>
@@ -42,7 +46,7 @@ namespace std {
 #       else
 			using namespace nana::experimental::filesystem::v1;
 #       endif
-
+#define NANA_USING_NANA_FILESYSTEM  true
 		} // filesystem
 	} // experimental
 } // std
@@ -56,12 +60,14 @@ namespace std {
 	namespace experimental {
 		namespace filesystem {
                   using namespace boost::filesystem;
+#define NANA_USING_BOOST_FILESYSTEM true
 		} // filesystem
 	} // experimental
 } // std
 
 #else
 #    include <experimental/filesystem>
+#define NANA_USING_STD_FILESYSTEM true
 #endif
 
 #ifndef __cpp_lib_experimental_filesystem