IPADM_NVP_IFCLASS
if ((err = nvlist_add_string(nvl, IPADM_NVP_IFCLASS, strval)) != 0)
if (nvlist_exists(db_nvl, IPADM_NVP_IFCLASS) &&
IPADM_NVP_IFCLASS, &strval) == 0)
if (nvlist_lookup_string(nvl, IPADM_NVP_IFCLASS,