#include <sstream>
#include <mpi.h>;

using std::string;

int main(int argc, char *argv[])
{
  int          myrank;
  if (MPI_Init(&argc,&argv)!=MPI_SUCCESS)
  {
    printf("MPI_Init failed");
  }
  MPI_Comm_rank(MPI_COMM_WORLD, &myrank);

  int world_size, universe_size, *universe_sizep, flag;
  MPI_Comm_size(MPI_COMM_WORLD, &world_size);
  printf("world_size %d\n",world_size);

  MPI_Attr_get(MPI_COMM_WORLD, MPI_UNIVERSE_SIZE,
  &universe_sizep, &flag);

  if (!flag)
  {
    printf("This MPI does not support UNIVERSE_SIZE. How many processes total?");
    scanf("%d", &universe_size);
  } else universe_size = *universe_sizep;
  printf("universe size %d\n",universe_size);

  char* hiargv[1];
  char* m0=" ";
  hiargv[0]=m0;

  MPI_Comm childComm;
  int spawnerror;
  printf("try to spawn\n");
  MPI_Comm_spawn("./hi",hiargv, universe_size-1, MPI_INFO_NULL, myrank, MPI_COMM_SELF, &childComm, &spawnerror);
  printf("after spawn\n");
  MPI_Finalize();
  return 0;
}