curl WRITEFUNCTION and classes

Question

class Filter{
private:
    string contents;
    bool Server(void);
public:
    void handle(void *, size_t, size_t, void *);
   };

i have a class he

Answer 1

string temp;

curl_easy_setopt(curl,CURLOPT_WRITEFUNCTION,handle);
curl_easy_setopt(curl,CURLOPT_WRITEDATA,&temp);

size_t Filter::handle(void *ptr, size_t size, size_t nmemb, string stream)
{
    string temp(static_cast<const char*>(ptr), size * nmemb);
    stream = temp;
    return size*nmemb;
}

thats how i got it to work.. this will save the website to the string named temp.

Answer 2

handle must be a static member function. You can pass a pointer to the instance of Filter as last argument by using CURLOPT_WRITEDATA

class Filter
{ 
private:
    std::string content_;
    static size_t handle(char * data, size_t size, size_t nmemb, void * p);
    size_t handle_impl(char * data, size_t size, size_t nmemb);
};

size_t Filter::handle(char * data, size_t size, size_t nmemb, void * p)
{
    return static_cast<Filter*>(p)->handle_impl(data, size, nmemb);
}

size_t Filter::handle_impl(char* data, size_t size, size_t nmemb)
{
    content_.append(data, size * nmemb);
    return size * nmemb;
}

int main()
{
   // curl initialization... should be done in a constructor
   Filter f;
   curl_easy_setopt(curl, CURLOPT_WRITEDATA, &f);
   curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, &Filter::handle);
   // curl cleanup... should be done in a destructor
   return 0;
}

Answer 3

I am using curlpp:

std::stringstream result;

request.setOpt(cURLpp::Options::WriteStream(&result));
request.perform();

this will save the reply webserver to the stringstream named result.