leaky_walk_init
leaky_walk_init, leaky_walk_step, leaky_walk_fini },
leaky_walk_init, leaky_buf_walk_step, leaky_walk_fini },
extern int leaky_walk_init(mdb_walk_state_t *);
leaky_walk_init, leaky_walk_step, leaky_walk_fini },
leaky_walk_init, leaky_buf_walk_step, leaky_walk_fini },