diff --git a/src/mfm_dup.cpp b/src/mfm_dup.cpp
index 03f75474..41027c7f 100644
--- a/src/mfm_dup.cpp
+++ b/src/mfm_dup.cpp
@@ -9,7 +9,7 @@
 
 
 
-namespace fs = std::filesystem;
+namespace stdfs = std::filesystem;
 
 namespace mfm
 {