diff --git a/src/fios.h b/src/fios.h
--- a/src/fios.h
+++ b/src/fios.h
@@ -223,6 +223,6 @@ bool FiosDelete(const char *name);
 std::string FiosMakeHeightmapName(const char *name);
 std::string FiosMakeSavegameName(const char *name);
 
-FiosType FiosGetSavegameListCallback(SaveLoadOperation fop, const char *file, const char *ext, char *title, const char *last);
+FiosType FiosGetSavegameListCallback(SaveLoadOperation fop, const std::string &file, const char *ext, char *title, const char *last);
 
 #endif /* FIOS_H */