-void lttv_toolbars_add(LttvToolbars *h, lttvwindow_viewer_constructor f, char* tooltip, char ** pixmap);
+LttvToolbarClosure lttv_toolbars_add(LttvToolbars *h,
+ lttvwindow_viewer_constructor f,
+ char* tooltip,
+ char ** pixmap,
+ GtkWidget *widget);