/* file: hello.c
   compile: cc -64 hello.c -lmpi
   run: mpirun -np 2 ./a.out
*/
#include "mpi.h" 
main( argc, argv ) 
int argc; 
char **argv; 
{ 
    char message[20]; 
    int myrank; 
    MPI_Status status; 
    MPI_Init( &argc, &argv ); 
    MPI_Comm_rank( MPI_COMM_WORLD, &myrank ); 
    if (myrank == 0)    /* code for process zero */ 
      { 
        strcpy(message,"Hello, there"); 
        MPI_Send(message, strlen(message)+1, MPI_CHAR, 1, 99, MPI_COMM_WORLD); 
      } 
    else                /* code for process one */ 
      { 
        MPI_Recv(message, 20, MPI_CHAR, 0, 99, MPI_COMM_WORLD, &status); 
        printf("rank%d received :%s\n", myrank, message); 
      } 
    MPI_Finalize(); 
  }