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/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
#include "mpi.h"
#include <stdio.h>
#include <string.h>
#define BUFLEN 512
int main(int argc, char *argv[])
{
int myid, numprocs, next, namelen;
char buffer[BUFLEN], processor_name[MPI_MAX_PROCESSOR_NAME];
MPI_Status status;
MPI_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &numprocs);
MPI_Comm_rank(MPI_COMM_WORLD, &myid);
MPI_Get_processor_name(processor_name, &namelen);
fprintf(stderr, "Process %d on %s\n", myid, processor_name);
fprintf(stderr, "Process %d of %d\n", myid, numprocs);
strcpy(buffer, "hello there");
if (myid == numprocs - 1)
next = 0;
else
next = myid + 1;
if (myid == 0) {
printf("%d sending '%s' \n", myid, buffer);
fflush(stdout);
MPI_Send(buffer, strlen(buffer) + 1, MPI_CHAR, next, 99, MPI_COMM_WORLD);
printf("%d receiving \n", myid);
fflush(stdout);
MPI_Recv(buffer, BUFLEN, MPI_CHAR, MPI_ANY_SOURCE, 99, MPI_COMM_WORLD, &status);
printf("%d received '%s' \n", myid, buffer);
fflush(stdout);
/* mpdprintf(001,"%d receiving \n",myid); */
} else {
printf("%d receiving \n", myid);
fflush(stdout);
MPI_Recv(buffer, BUFLEN, MPI_CHAR, MPI_ANY_SOURCE, 99, MPI_COMM_WORLD, &status);
printf("%d received '%s' \n", myid, buffer);
fflush(stdout);
/* mpdprintf(001,"%d receiving \n",myid); */
MPI_Send(buffer, strlen(buffer) + 1, MPI_CHAR, next, 99, MPI_COMM_WORLD);
printf("%d sent '%s' \n", myid, buffer);
fflush(stdout);
}
MPI_Barrier(MPI_COMM_WORLD);
MPI_Finalize();
return (0);
}
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