Use opened body.out file and write content to it.

  curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, write_data);

  /* open the files */

  headerfile = fopen(headerfilename,"w");

  headerfile = fopen(headerfilename,"wb");

  if (headerfile == NULL) {

    curl_easy_cleanup(curl_handle);

    return -1;

  }

  bodyfile = fopen(bodyfilename,"w");

  bodyfile = fopen(bodyfilename,"wb");

  if (bodyfile == NULL) {

    curl_easy_cleanup(curl_handle);

    return -1;

  }

  /* we want the headers to this file handle */

  /* we want the headers be written to this file handle */

  curl_easy_setopt(curl_handle,   CURLOPT_WRITEHEADER, headerfile);

  /*

   * Notice here that if you want the actual data sent anywhere else but

   * stdout, you should consider using the CURLOPT_WRITEDATA option.  */

  /* we want the body be written to this file handle instead of stdout */

  curl_easy_setopt(curl_handle,   CURLOPT_WRITEDATA, bodyfile);

  /* get it! */

  curl_easy_perform(curl_handle);

  /* close the header file */

  fclose(headerfile);

  /* close the body file */

  fclose(bodyfile);

  /* cleanup curl stuff */

  curl_easy_cleanup(curl_handle);