Parallel I/O

void Get_data(

float* a_ptr /* out */,

float* b_ptr /* out */,

int* n_ptr /* out */,

int my_rank /* in */,

int p /* in */) {

int source = 0; /* All local variables used by */

int dest; /* MPI_Send and MPI_Recv */

int tag;

MPI_Status status;

if (my_rank == 0){

printf("Enter a, b, and n\n");

scanf("%f %f %d", a_ptr, b_ptr, n_ptr);

for (dest = 1; dest < p; dest++){

tag = 0;

MPI_Send(a_ptr, 1, MPI_FLOAT,

dest, tag, MPI_COMM_WORLD);

tag = 1;

MPI_Send(b_ptr, 1, MPI_FLOAT, dest, tag,

MPI_COMM_WORLD);

tag = 2;

MPI_Send(n_ptr, 1, MPI_INT, dest, tag,

MPI_COMM_WORLD);

}

} else {

tag = 0;

MPI_Recv(a_ptr, 1, MPI_FLOAT, source, tag,

MPI_COMM_WORLD, &status);

tag = 1;

MPI_Recv(b_ptr, 1, MPI_FLOAT, source, tag,

MPI_COMM_WORLD, &status);

tag = 2;

MPI_Recv(n_ptr, 1, MPI_INT, source, tag,

MPI_COMM_WORLD, &status);

}

} /* Get_data */

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