next_flush (void *nxdata, uint32_t flags, int *err)
{
  struct b_conn *b_conn = nxdata;
  int r;

  r = b_conn->b->flush (b_conn->b, b_conn->conn, flags, err);
  if (r == -1)
    assert (*err);
  return r;
}
next_flush (void *nxdata, uint32_t flags, int *err)
{
  struct b_conn *b_conn = nxdata;
  int r;

  r = b_conn->b->flush (b_conn->b, b_conn->conn, flags, err);
  if (r == -1)
    assert (*err);
  return r;
}