trns_proc_func *, trns_free_func *, void *);
size_t trns_chain_next (struct trns_chain *);
enum trns_result trns_chain_execute (const struct trns_chain *,
trns_proc_func *, trns_free_func *, void *);
size_t trns_chain_next (struct trns_chain *);
enum trns_result trns_chain_execute (const struct trns_chain *,