data_read_id_max
dp = data_read_id_max(dp, &id, 0, numschemata, &data);
dp = data_read_id_max(dp, &did, idmap, numid + numrel, &data);
dp = data_read_id_max(dp, &nentries, 0, 0, &data);
dp = data_read_id_max(dp, &id, 0, numschemata, &data);
dp = data_read_id_max(dp, &id, 0, 0, &data);
dp = data_read_id_max(dp, &id, 0, numschemata, &data);