MPIstudent.c

#include "mpi.h"
#include <stdio.h>
#include <string.h>

int main(int argc, char *argv[])
{
    int i, j, myrank;
    MPI_Init(&argc, &argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &myrank);
#include "mpistudent.h"
    if (myrank == 0) {
        struct student bclass[2]; /* Just known to rank 0 */
        strncpy(bclass[0].name, "Joe Jones", 30);
        strncpy(bclass[0].year, "Sr.", 10);;
        bclass[0].exam_grade=95;
        strncpy(bclass[1].name, "Sam Smith", 30);
        strncpy(bclass[1].year, "Frosh.", 10);;
        bclass[1].exam_grade=90;
        MPI_Send(&bclass, 2, MPI_STUDENT, 1, 123, MPI_COMM_WORLD);
    } else if (myrank == 1) {
        struct student cclass[2]; /* Just known to rank 1 */
        MPI_Recv(&cclass, 2, MPI_STUDENT, 0, 123, MPI_COMM_WORLD, &status);
        printf("%s \n",cclass[1].name);
        printf("%s \n",cclass[1].year);
        printf("%i \n",cclass[1].exam_grade);
    }
    MPI_Finalize();
    return 0;
}

mpistudent.h

struct student {
    char name[30];
    char year[10]; /*Fresh. Soph.,Jr. Sr.*/
    int exam_grade;
};
MPI_Status status;
MPI_Datatype MPI_STUDENT;
MPI_Datatype type[3] = { MPI_CHAR, MPI_CHAR, MPI_INT}; /* The "MPI types" of student*/
int blocklen[3] = { 30, 10, 1};   /* The array lengths */
MPI_Aint disp[3]={0,32,44};    /* Address displacements */
MPI_Type_create_struct(3, blocklen, disp, type, &MPI_STUDENT);
MPI_Type_commit(&MPI_STUDENT);