#include <mpi.h>
#include <stdlib.h>

  int attr;
  int flg;

int PetscCommDuplicate(MPI_Comm comm)
{
     void *pointer;
    MPI_Attr_get(comm,attr,&pointer,&flg);
        if (!flg) abort();
    return 0;
}

int main(int argc,char **args)
{

  int n = 1000000,i,k,kn = 1000;
  double *array;
  MPI_Comm comm;
  void *pointer;
  int a;

  MPI_Init(&argc,&args);
  MPI_Comm_dup(MPI_COMM_WORLD,&comm);
  MPI_Keyval_create(MPI_NULL_COPY_FN,MPI_NULL_DELETE_FN,&attr,(void*)0);
  
  array = (double*) malloc(n*sizeof(double));

  for (i=0; i<n; i++) array[i] = i;

  MPI_Attr_put(comm,attr,&a);
  MPI_Attr_get(comm,attr,&pointer,&flg);
  if (!flg) abort();

  for (k=0; k<kn; k++) {
    for (i=0; i<n; i++) array[i] += array[i];
    PetscCommDuplicate(comm);
    if (!flg) abort();
  }
  
  free(array);
  MPI_Finalize();
  return 0;
}