add_transformation (struct dataset *ds, trns_proc_func *proc, trns_free_func *free, void *aux)
{
trns_chain_append (ds->cur_trns_chain, NULL, proc, free, aux);
add_transformation (struct dataset *ds, trns_proc_func *proc, trns_free_func *free, void *aux)
{
trns_chain_append (ds->cur_trns_chain, NULL, proc, free, aux);