curl_easy_setopt(curl, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.1) Gecko/20061204 Firefox/2.0.0.1");
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writer);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, &body);
curl_easy_setopt(curl, CURLOPT_URL, "http://url");
curl_easy_setopt(curl, CURLOPT_HEADER,1);
curl_easy_setopt(curl, CURLOPT_POST, 1);
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "запрос");
curl_easy_setopt(curl, CURLOPT_COOKIEFILE, &cookies);
curl_easy_perform(curl); // посылаем

static int writer(char *data, size_t size, size_t nmemb, string *buffer)
{
  int result = 0;

  if (buffer != NULL)
  {
    buffer->append(data, size * nmemb);
    result = size * nmemb;
  }

  return result;
}