问Curl命令行工作，C++ curl库不工作。

EN

curl -X POST -H 'Accept: application/json' -H 'Content-Type: application/json' -H 'Authorization: <some_hash_value>' -k <my_full_url> -data '<my_json_string>'

void performRequest(const std::string& json, const void* userData, CallbackFunction callback)
{
    struct curl_slist* headers = NULL;

    headers = curl_slist_append(headers, "Accept: application/json");
    headers = curl_slist_append(headers, "Content-Type: application/json");
    headers = curl_slist_append(headers, (std::string("Authorization: ") + m_authorization).c_str());

    CURL* curlHandle = curl_easy_init();
    if (!curlHandle)
    {
        std::cerr << "Curl handler initialization failed";
    }

    curl_easy_setopt(curlHandle, CURLOPT_NOSIGNAL, 1);
    curl_easy_setopt(curlHandle, CURLOPT_HTTPHEADER, headers);

    // specify target URL, and note that this URL should include a file name, not only a directory
     curl_easy_setopt(curlHandle, CURLOPT_URL, m_url.c_str());

    // enable uploading
    curl_easy_setopt(curlHandle, CURLOPT_UPLOAD, 1L);

    // set HTTP method to POST
    curl_easy_setopt(curlHandle, CURLOPT_CUSTOMREQUEST, "POST");

    // set json data; I use EXACTLY the same string as in command line
    curl_easy_setopt(curlHandle, CURLOPT_COPYPOSTFIELDS, json.c_str());

    // set data size
    curl_easy_setopt(curlHandle, CURLOPT_POSTFIELDSIZE_LARGE, json.size());

    // set user data for getting it in response
    curl_easy_setopt(curlHandle, CURLOPT_WRITEDATA, userData);    // pointer to a custom struct

    // set callback function for getting response
    curl_easy_setopt(curlHandle, CURLOPT_WRITEFUNCTION, callback);    // some callback

    // send request
    curl_easy_perform(curlHandle);

    curl_easy_cleanup(curlHandle);
    curl_slist_free_all(headers);
}