id_off
id_off = 0;
id_tbl[i].offset = id_off + ids_top;
(void) memcpy(ids + id_off, m[i].id, m[i].id_len);
id_off += m[i].id_len;
size_t id_len, str_len, id_off, str_off, ids_top, strs_top;
id_off = 0;
id_tbl[i].offset = doswap(id_off + ids_top);
(void) memcpy(ids + id_off, m[i].id, m[i].id_len);
id_off += m[i].id_len;
size_t id_len, str_len, id_off, str_off, ids_top, strs_top;