idm_get_next_listvalue
am_choice = idm_get_next_listvalue(nvp, NULL);
am_choice = idm_get_next_listvalue(nvp, am_choice);
alg_choice = idm_get_next_listvalue(nvp, NULL);
alg_choice = idm_get_next_listvalue(nvp, alg_choice);
digest_choice = idm_get_next_listvalue(choices, NULL);
digest_choice = idm_get_next_listvalue(choices,
vchoice = idm_get_next_listvalue(nvp, NULL);
vchoice = idm_get_next_listvalue(nvp, vchoice);
idm_get_next_listvalue(nvpair_t *value_list, nvpair_t *curr_nvp);