#include "mpi.h" #include <string> int main(int argc, char **argv) { MPI_Init(&argc, &argv); int rank, size; MPI_Comm_rank(MPI_COMM_WORLD, &rank); MPI_Comm_size(MPI_COMM_WORLD, &size); std::string data = "xyyzzz"; int length[3] = { 1, 2, 3 }; MPI_Aint displacement[3] = { rank, size + 2 * rank, 3 * size + 3 * rank }; MPI_Datatype dtype; MPI_Type_create_hindexed(3, length, displacement, MPI_CHAR, &dtype); MPI_Type_commit(&dtype); MPI_File MPIfile; if (MPI_File_open(MPI_COMM_WORLD, "output.txt", MPI_MODE_WRONLY | MPI_MODE_CREATE, MPI_INFO_NULL, &MPIfile)) { printf("MPI cannot create file\n"); } else { MPI_File_set_view(MPIfile, 0, MPI_CHAR, dtype, "native", MPI_INFO_NULL); MPI_File_write_all(MPIfile, data.c_str(), data.size(), MPI_CHAR, MPI_STATUS_IGNORE); MPI_File_close(&MPIfile); } MPI_Finalize(); return 0; }