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Forked from varun-nagaraja/mpi_sample.c
Created April 5, 2019 13:59
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Sample MPI Program
#include <stdio.h>
#include <string.h>
#include "mpi.h"
int main(int argc, char* argv[]){
int my_rank; /* rank of process */
int p; /* number of processes */
int source; /* rank of sender */
int dest; /* rank of receiver */
int tag=0; /* tag for messages */
char message[100]; /* storage for message */
MPI_Status status ; /* return status for receive */
/* start up MPI */
MPI_Init(&argc, &argv);
/* find out process rank */
MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
/* find out number of processes */
MPI_Comm_size(MPI_COMM_WORLD, &p);
if (my_rank !=0){
/* create message */
sprintf(message, "Hello MPI World from process %d!", my_rank);
dest = 0;
/* use strlen+1 so that '\0' get transmitted */
MPI_Send(message, strlen(message)+1, MPI_CHAR,
dest, tag, MPI_COMM_WORLD);
}
else{
printf("Hello MPI World From process 0: Num processes: %d\n",p);
for (source = 1; source < p; source++) {
MPI_Recv(message, 100, MPI_CHAR, source, tag,
MPI_COMM_WORLD, &status);
printf("%s\n",message);
}
}
/* shut down MPI */
MPI_Finalize();
return 0;
}
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