Function write_callback

main/interface/network/RequestObject.cpp:16–18

    //class request_failed end.

    size_t write_callback(char* char_ptr, size_t batch, size_t size, const std::function<size_t(char*, size_t, size_t)>* callback) {
        return (*callback)(char_ptr, batch, size);
    }

    int progress_callback(const std::function<int(curl_off_t, curl_off_t, curl_off_t, curl_off_t)>* callback,
                          curl_off_t dl_total, curl_off_t dl_now, curl_off_t ul_total, curl_off_t ul_now) {