class IO {

public:
  // constructor
  IO(int, int, int, int, Range );

private:
  Partitioning_Type Guard;
  Partitioning_Type noGuard;
  FloatARRAY D_VAR;
  FloatARRAY D_VARG;

  friend class MHD;
  friend class ION;
  // input/output routines
friend  int dump_step(int, MHD*, ION*, int*, FLoaT*, IO& );
friend  int read_step(int, int*, FLoaT*, MHD*, ION*, IO&);

};