sendrecv.c

刚才是说明 现在是安装程序在 LINUX环境下进行编程的MPICH安装文件

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

#define BIG_SIZE 100*1024

int main(int argc, char *argv[])
{
    int size, rank;
    char buffer[100] = "garbage";
    char big_buffer[BIG_SIZE] = "big garbage";
    /*MPI_Request request; */
    MPI_Status status;
    int tag = 1;
    int reps = 1;
    int i;
    
    printf("Simple Send/Recv test.\n"); fflush(stdout);
    
    MPI_Init(&argc, &argv);
    MPI_Comm_size(MPI_COMM_WORLD, &size);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    
    if (size < 2)
    {
	printf("Two processes needed.\n");
	MPI_Finalize();
	return 0;
    }
    
    if (argc > 1)
    {
	reps = atoi(argv[1]);
	if (reps < 1)
	    reps = 1;
    }
    
    if (rank == 0)
    {
	printf("Rank 0: sending messages to process 1.\n"); fflush(stdout);
	strcpy(buffer, "Hello process one.");
	for (i = 0; i<reps; i++)
	{
	    /*MPI_Isend(buffer, 100, MPI_BYTE, 1, tag, MPI_COMM_WORLD, &request);
	    MPI_Wait(&request, &status); */
	    MPI_Send(buffer, 100, MPI_BYTE, 1, tag, MPI_COMM_WORLD);
	    MPI_Recv(buffer, 100, MPI_BYTE, 1, tag, MPI_COMM_WORLD, &status);
	}
	strcpy(big_buffer, "Hello again process one.");
	for (i = 0; i<reps; i++)
	{
	    /*MPI_Isend(buffer, 100, MPI_BYTE, 1, tag, MPI_COMM_WORLD, &request);
	    MPI_Wait(&request, &status); */
	    MPI_Send(big_buffer, BIG_SIZE, MPI_BYTE, 1, tag, MPI_COMM_WORLD);
	    MPI_Recv(big_buffer, BIG_SIZE, MPI_BYTE, 1, tag, MPI_COMM_WORLD, &status);
	}
    }
    else if (rank == 1)
    {
	printf("Rank 1: receiving messages from process 0.\n"); fflush(stdout);
	for (i = 0; i<reps; i++)
	{
	    /*MPI_Irecv(buffer, 100, MPI_BYTE, 0, tag, MPI_COMM_WORLD, &request);
	    MPI_Wait(&request, &status); */
	    MPI_Recv(buffer, 100, MPI_BYTE, 0, tag, MPI_COMM_WORLD, &status);
	    MPI_Send(buffer, 100, MPI_BYTE, 0, tag, MPI_COMM_WORLD);
	}
	printf("Rank 1: received message '%s'\n", buffer); fflush(stdout);
	for (i = 0; i<reps; i++)
	{
	    /*MPI_Irecv(buffer, 100, MPI_BYTE, 0, tag, MPI_COMM_WORLD, &request);
	    MPI_Wait(&request, &status); */
	    MPI_Recv(big_buffer, BIG_SIZE, MPI_BYTE, 0, tag, MPI_COMM_WORLD, &status);
	    MPI_Send(big_buffer, BIG_SIZE, MPI_BYTE, 0, tag, MPI_COMM_WORLD);
	}
	printf("Rank 1: received message '%s'\n", big_buffer); fflush(stdout);
    }
    else
    {
	printf("Rank %d, I am not participating.\n", rank); fflush(stdout);
    }
    
    MPI_Finalize();
    return 0;
}