63 lines
1.8 KiB
C
Executable File
63 lines
1.8 KiB
C
Executable File
#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include <mpi.h>
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#define TAG 0 /* Message tag. */
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int main(int argc, char *argv[]) {
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char * buff = NULL;
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int rank;
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/* Start with MPI_Init and get the rank. */
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MPI_Init(&argc,&argv);
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MPI_Comm_rank(MPI_COMM_WORLD, &rank);
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/***********************************************************************
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* MASTER PROCESS *
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***********************************************************************/
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if(rank == 0) {
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int size, i;
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buff = (char *)calloc(128, sizeof(char));
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/* Get the number of processes. */
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MPI_Comm_size(MPI_COMM_WORLD, &size);
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printf("MASTER: %d processes available.\n", size);
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/* Send data to the slaves. */
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for(i = 1; i < size; i++) {
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memset(buff, 0, 128);
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sprintf(buff, "Hello, Process %d!", i);
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MPI_Send(buff, strlen(buff) + 1, MPI_CHAR, i, TAG, MPI_COMM_WORLD);
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}
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/***********************************************************************
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* SLAVE PROCESS *
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***********************************************************************/
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} else {
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MPI_Status status;
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int data_size;
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/* Probe orders from the master. */
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MPI_Probe(0 /*Master's rank*/, TAG, MPI_COMM_WORLD, &status);
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/* Find the amount of data sent by the master and allocate memory for it. */
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MPI_Get_count(&status, MPI_CHAR, &data_size);
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buff = (char *)calloc(data_size, sizeof(char));
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/* Actually receive the data. */
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MPI_Recv(buff, data_size, MPI_CHAR, 0 /*Master's rank*/, TAG, MPI_COMM_WORLD, &status);
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printf("SLAVE %d: Master says: \"%s\"\n", rank, buff);
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}
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/* Clean up. */
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if(buff != NULL)
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free(buff);
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/* End with MPI_Finalize. */
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MPI_Finalize();
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return EXIT_SUCCESS;
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}
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