diff --git a/bin/ltlsynt.cc b/bin/ltlsynt.cc
index e0cf78c47..630ccd629 100644
--- a/bin/ltlsynt.cc
+++ b/bin/ltlsynt.cc
@@ -705,7 +705,7 @@ namespace
         }
 
       if (opt_csv)
-        print_csv(f);
+        print_csv(f, filename);
       return res;
     }