diff --git a/src/conio/ciolib.c b/src/conio/ciolib.c
index 7742eb2ef2b7a49b1139cec7eed442b1cf7feea7..dbe5f3360fd91394afead81798a7a17857d6093c 100644
--- a/src/conio/ciolib.c
+++ b/src/conio/ciolib.c
@@ -81,7 +81,7 @@ CIOLIBEXPORT int directvideo=0;
 CIOLIBEXPORT int hold_update=0;
 CIOLIBEXPORT int puttext_can_move=0;
 CIOLIBEXPORT int ciolib_reaper=TRUE;
-CIOLIBEXPORT char *ciolib_appname=NULL;
+CIOLIBEXPORT const char *ciolib_appname=NULL;
 CIOLIBEXPORT int ciolib_initial_window_height = -1;
 CIOLIBEXPORT int ciolib_initial_window_width = -1;
 static int initialized=0;