C++ code:

__attribute__ ((noinline))
size_t count_returns(char * data, size_t length) {
    size_t answer = 0;
    for(size_t i = 0; i < length; i++) {
      if (data[i] == '\n') answer++;
    }
    return answer;
}

void count_lines_benchmark(size_t size) {
    printf(" %s\n", __PRETTY_FUNCTION__);
    bool verbose = true;
    printf("generating and parsing input having %zu bytes.\n", size);
    int repeat = 10;
    std::vector<char> blob(size + 1, 'a');
    blob [size] = '\0';
    // average line length should be 80
    for(size_t br = 0; br < size / 80; br++) {
      blob[rand() % size] = '\n';
    }
    size_t c = 0;
    BEST_TIME_NS((c = count_returns(blob.data(), blob.size())), , repeat, size, verbose);
    printf("bogus = %zu \n", c);
}

int main(int argc, char** argv) {
  count_lines_benchmark(10000000);
  get_line_benchmark(10000000);
  get_line_predictable_benchmark(10000000);
  return EXIT_SUCCESS;
}