#include <stdio.h>
#include <unistd.h>
#include <limits.h>
#include "mpi.h"
#include "io.h"
int main(int argc, char** argv) {
  int me, nproc, io_clone, input;
  char hostname[PATH_MAX];
  MPI_Init(&argc, &argv);
  MPI_Comm_rank(MPI_COMM_WORLD, &me);
  MPI_Comm_size(MPI_COMM_WORLD, &nproc);
  if((io_clone = get_io_clone()) < 0){
    fprintf(stderr, "No one can do IO!\n");
    goto exit; 
  }
  if(gethostname(hostname, PATH_MAX) != 0){
    fprintf(stderr, "gethostname failed, exiting\n");
    goto exit; 
  }
  if(me == io_clone){
    fprintf(stderr, "I'm clone %3d on %s an I can do IO!\n", me, hostname);
    fprintf(stderr, "Give me a number\n");
    scanf("%d", &input);
    fprintf(stderr, "You gave me %d\n", input);
  }
  //N.B. It is vital, for this next line to make sense, that 
  //get_io_clone() returns the same value in all clones! 
  //Hence the election process.
  MPI_Bcast(&input, 1, MPI_INT, io_clone, MPI_COMM_WORLD);

  fprintf(stderr, "Clone %3d input = %d!\n", me, input);

 exit:
  MPI_Finalize();
  return 0;
}