double AU;
t_calcephbin *peph;

/* open the ephemeris file */
peph = calceph_open("example1.dat");
if (peph)
{
  /* print the value of AU */
  if (calceph_getconstant(peph, "AU", &AU))
      printf("AU=%23.16E\n", AU);

  /* close the ephemeris file */
  calceph_close(peph);
}