curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
curl_easy_setopt(curl, CURLOPT_FILE, NULL);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
curl_easy_setopt(curl, CURLOPT_FILE, NULL);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);