diff --git a/macro.c b/macro.c
index b3a3e03a..7924c9bf 100644
--- a/macro.c
+++ b/macro.c
@@ -323,6 +323,8 @@ Tcl_Interp *MacroInit(SicsInterp * pSics)
   assert(pSics);
 
   /* create interpreter and unknown */
+  extern const char *argv0;
+  Tcl_FindExecutable(argv0);
   pInter = Tcl_CreateInterp();
   pUnknown = (struct __SicsUnknown *) malloc(sizeof(struct __SicsUnknown));
   if ((!pInter) || (!pUnknown)) {