blob: dc569dd111b030ab95aaf348103a14c9500b1d6c [file] [log] [blame]
#include "mpi.h"
#include <iostream>
using namespace std;
// from ews/gridmpi/mpiExample2/src/helloMPI.c
class HelloWorld {
public:
int sayHello(int argc, char* argv[]);
};
int HelloWorld::sayHello(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 */
cout << "Hello MPI World the original." << endl;
/* start up MPI */
MPI_Init(&argc, (char***)(&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, "Greetings 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("From process 0: Num processes: %d\n",p);
for (source = 1; source < p; source++) {
MPI_Recv(message, 100, MPI_INTEGER, source, tag,
MPI_COMM_WORLD, &status);
cout << message << endl;
}
}
/* shut down MPI */
MPI_Finalize();
return 0;
}
int main (int argc, char* argv[]) {
HelloWorld hello;
hello.sayHello(argc, argv);
return 0;
}