void cancel();
void ref();
void set_nbc_requests(MPI_Request* reqs, int size);
+ int get_nbc_requests_size();
+ MPI_Request* get_nbc_requests();
static void finish_wait(MPI_Request* request, MPI_Status* status);
static void unref(MPI_Request* request);
static int wait(MPI_Request* req, MPI_Status* status);