int main(int argc, char** argv) {
  struct FrontendConfig frontend_config;
  FrontendFillConfigWithDefaults(&frontend_config);

  char* filename = argv[1];  // argc在没有被检查的情况下将argv[1]的内容赋值给了指针并在fprintf中使用。
  int sample_rate = 16000;

  struct FrontendState frontend_state;
  if (!FrontendPopulateState(&frontend_config, &frontend_state, sample_rate)) {
    fprintf(stderr, "Failed to populate frontend state\n");
    FrontendFreeStateContents(&frontend_state);
    return 1;
  }

  FILE* fp = fopen(filename, "r");
  if (fp == NULL) {
    fprintf(stderr, "Failed to open %s for read\n", filename);
    return 1;
  }
  fseek(fp, 0L, SEEK_END);
  size_t audio_file_size = ftell(fp) / sizeof(int16_t);
  fseek(fp, 0L, SEEK_SET);
  int16_t* audio_data = malloc(audio_file_size * sizeof(int16_t));
  int16_t* original_audio_data = audio_data;
  if (audio_file_size !=
      fread(audio_data, sizeof(int16_t), audio_file_size, fp)) {
    fprintf(stderr, "Failed to read in all audio data\n");
    fclose(fp);
    return 1;
  }

  while (audio_file_size > 0) {
    size_t num_samples_read;
    struct FrontendOutput output = FrontendProcessSamples(
        &frontend_state, audio_data, audio_file_size, &num_samples_read);
    audio_data += num_samples_read;
    audio_file_size -= num_samples_read;

    if (output.values != NULL) {
      int i;
      for (i = 0; i < output.size; ++i) {
        printf("%d ", output.values[i]);
      }
      printf("\n");
    }
  }

  FrontendFreeStateContents(&frontend_state);
  free(original_audio_data);
  fclose(fp);
  return 0;
}