The example code (hello-mpi.cpp, downloaded from http://www.mpitutorial.com), which we will compile in this recipe, will initialize the MPI library, have every process print its name, and eventually finalize the library:
#include <iostream>#include <mpi.h>int main(int argc, char **argv) { // Initialize the MPI environment. The two arguments to MPI Init are not // currently used by MPI implementations, but are there in case future // implementations might need the arguments. MPI_Init(NULL, NULL); // Get the number of processes int world_size; MPI_Comm_size(MPI_COMM_WORLD, &world_size); // Get the rank of the process int world_rank; MPI_Comm_rank(MPI_COMM_WORLD, &world_rank); // Get the name of the processor char processor_name[MPI_MAX_PROCESSOR_NAME]; ...
