data_read_rel_idarray
dp = data_read_rel_idarray(dp, &idarraydatap, idmap, numid + numrel, &data, SOLVABLE_PREREQMARKER);
dp = data_read_rel_idarray(dp, &idarraydatap, idmap, numid + numrel, &data, SOLVABLE_FILEMARKER);
dp = data_read_rel_idarray(dp, &idarraydatap, idmap, numid + numrel, &data, 0);