int encdesc_read_header(GtEncdesc *encdesc, FILE *fp, GtError *err)
{
  int had_err = 0;
  GtUword cur_field_num;
  DescField *cur_field;

  had_err = encdesc_header_io_basics(encdesc, fp, gt_io_error_fread, err);

  if (!had_err)
    encdesc->fields = gt_calloc((size_t) encdesc->num_of_fields,
                                sizeof (DescField));

  for (cur_field_num = 0;
       !had_err && cur_field_num < encdesc->num_of_fields;
       cur_field_num++) {
    cur_field = &encdesc->fields[cur_field_num];
    /* cur_field->bits_per_num = 0; */
    /* cur_field->prev_value = 0; */
    had_err = io_field_sep_and_is_cons(cur_field, fp, gt_io_error_fread, err);

    if (!had_err && cur_field->is_cons) {
      had_err = io_cons_field_header(cur_field, fp, gt_io_error_fread, err);
    }
    else if (!had_err) {
      had_err = gt_io_error_fread_one(cur_field->is_numeric, fp, err);
      if (!had_err && cur_field->is_numeric) {
        had_err = io_numeric_field_header(cur_field, fp, gt_io_error_fread,
                                          err);
      }
      else if (!had_err) {
        had_err = io_field_len_header(cur_field, fp, gt_io_error_fread, err);

        if (!had_err) {
          cur_field->bittab = gt_bittab_new(cur_field->len);

          cur_field->data = gt_calloc((size_t) (cur_field->len + 1),
                                      sizeof (char));
          had_err = gt_io_error_fread(cur_field->data, sizeof (char),
                                      (size_t) cur_field->len, fp, err);

        }
        if (!had_err)
          had_err = read_field_header_bittab(cur_field, fp, err);

        if (!had_err) {
          cur_field->chars = gt_calloc((size_t) (cur_field->max_len + 1),
                                       sizeof (cur_field->chars));

          had_err = read_field_char_dists(cur_field, fp, err);
        }
      }
    }
  }
  return had_err;
}
static int gt_intset_read_type_rewind(FILE *fp, GtUword *type, GtError *err)
{
  int had_err = 0;
  fpos_t pos;
  if (fgetpos(fp, &pos) != 0) {
    gt_error_set(err, "fgetpos failed");
    had_err = 1;
  }
  if (!had_err)
    had_err = gt_io_error_fread(type, sizeof (*type), (size_t) 1, fp, err);
  if (!had_err && fsetpos(fp, &pos) != 0) {
    gt_error_set(err, "fsetpos failed");
    had_err = 1;
  }
  return had_err;
}