Function            rfloor - rounds down

  Syntax              long rfloor(struct REAL rx);

  Prototype in        real.h

  Remarks             rfloor finds the largest integer not greater than
                      rx.

                      Refer to the section SIMULATED FP MATH for further
                      details.

  Return value        rfloor returns the integer found (as a long).

  See also            _r_minpre, _rmatherr
                      radd(), rceil(), rdiv(), rnegate(), rnormalize(),
                      rsign(), rsub()