rem: }
add: gtk_tree_set_row_drag_data (selection_data, categ_tree_model, path);
context: gboolean categ_drag_data_get ( GtkTreeDragSource * drag_source, GtkTreePath * path,			       GtkSelectionData * selection_data ){    if ( path )    {	GtkTreeIter iter;	gint no_categ, no_sub_categ;	gpointer pointer;	if ( gtk_tree_model_get_iter ( GTK_TREE_MODEL(categ_tree_model), &iter, path ) )	{	    gtk_tree_model_get ( GTK_TREE_MODEL(categ_tree_model), &iter,				 CATEGORY_TREE_NO_CATEG_COLUMN, &no_categ, 				 CATEGORY_TREE_NO_SUB_CATEG_COLUMN, &no_sub_categ, 				 CATEGORY_TREE_POINTER_COLUMN, &pointer, 				 -1 );/* 	    gtk_selection_data_set (selection_data, GDK_SELECTION_TYPE_INTEGER, *//* 				    32, pointer, sizeof(gpointer) ); */	}    }    return TRUE;}