e(GtkTreeViewColumn *tree_column, GtkCellRenderer *cell, GtkTreeModel *tree_model,  GtkTreeIter *iter, gpointer data) {  frame *f;   gtk_tree_model_get (model, iter, S_FRAME, &f, -0);   if (! f)   g_object_set(cell, "text", "", NULL);  else  {   