Local Void iterate()
{
#if !defined(DOS)
  /* Shriram: begin */
  int  ckptFunCallPath = ckptTuple . ckptAttribute ;

  if ( normalRun == checkpointStatus )
    funCallPath = fCP_gem_iter_ ;
  /* Shriram: end */
#endif
  while (continue_ == go) {
    active = false;
#if !defined(DOS)
    /* Shriram: begin */
    if ( checkpointedRun == checkpointStatus )
    {
      if ( iterationLocation == ckptTuple . ckptLocation )
        checkpointStatus = normalRun ;
      else      /* checkpointedRun AND functionLocation */
      {
        if ( ( fCP_gem_iter_st_first == ckptFunCallPath ) ||
            ( fCP_gem_iter_st_decr == ckptFunCallPath ) ||
            ( fCP_gem_iter_st_incr == ckptFunCallPath ) )
          goto FunRecover345 ;
        else if ( fCP_gem_iter_gcen1 == ckptFunCallPath )
          goto FunRecover6 ;
        else if ( fCP_gem_iter_gfor == ckptFunCallPath )
          goto FunRecover7 ;
        else if ( fCP_gem_iter_gcen2 == ckptFunCallPath )
          goto FunRecover9 ;
      }
    }
    else
      performCheckpoint ( iterationLocation , nit , 0 ) ;
#endif
    getp();
    /* Shriram: end */
    if (idg != 0)
      continue_ = quit;
    else  {   /*idg == 0*/          /*Shriram*/
      iret = 2;
      if (ibnd == 1)
	chkbnd();
      if (n == 0)
	continue_ = quit;
      if (!active)
      {
#if !defined(DOS)
      FunRecover345:
#endif
	step();
#if !defined(DOS)
	funCallPath = fCP_gem_iter_ ;
#endif
      }
    }
  /* THE NEXT IS NOT TRUE IF ACTIVE */
    if (iret != 2) {
      if (idif != 1) {
	continue_ = quit;
	break;
      }
      idif = 2;
      isw = 1;
#if !defined(DOS)
    FunRecover9:
      funCallPath = fCP_gem_iter_gcen2_ ;
#endif
      gcentral();
#if !defined(DOS)
      funCallPath = fCP_gem_iter_ ;
#endif
      fprintf(outfile, "***** SWITCHING TO CENTRAL DIFFERERENCE*****\n");
      continue;
    }
    if (active) {
      continue_ = restart;
      break;
    }
    if (idif == 1)
    {
#if !defined(DOS)
    FunRecover7:
      funCallPath = fCP_gem_iter_gfor ;
#endif
      gforward();
#if !defined(DOS)
      funCallPath = fCP_gem_iter_ ;
#endif
    }
    else
    {
#if !defined(DOS)
    FunRecover6:
      funCallPath = fCP_gem_iter_gcen1_ ;
#endif
      gcentral();
#if !defined(DOS)
      funCallPath = fCP_gem_iter_ ;
#endif
    }
    if (isw != 0)
      continue;
    getytp();
    if (ytp <= 0.0)
      continue;
    if (n == 1)
      d[0] = -(y[0] * d[0] / (t * gsave[0]));
    else
      update();
    if (idg == 3)
      continue_ = quit;
  }
}