HKEYDATA_SIZE
new_datalen = old_len - HKEYDATA_SIZE(0) + add_len;
HOFFDUP_SIZE : HKEYDATA_SIZE(new_datalen);
off = HOFFSET(p) - HKEYDATA_SIZE(dbt->size);
pg->inp[indx] - HKEYDATA_SIZE(0))
(HKEYDATA_SIZE(len) + sizeof(db_indx_t))