keep-alive curl C htttps POST

Question

With this code I am sending strings to a webserver using libcurl and write the data to a MySQL (is done at the webserver). My Problem is that for every call of this function the program starts a new key exchange with the webserver. I would like to have a persistant connection to the Server. I searched here and web already and didnt find any satisfying solutions. Multi-handler and forced keep alive still open a new connection.

Following is my Code to establish an SSL Connection:

CURL *curl;
CURLcode res;

res = curl_global_init(CURL_GLOBAL_DEFAULT);   // Check for errors 

if(res != CURLE_OK) {
    fprintf(stderr, "curl_global_init() failed: %s\n",
    curl_easy_strerror(res));
    return 1;
}

// curl handler 
curl = curl_easy_init();

if(curl) {
    curl_easy_setopt(curl, CURLOPT_POSTFIELDS, STRING);
    curl_easy_setopt(curl, CURLOPT_URL, "https://IP/something/something.php");
    curl_easy_setopt(curl, CURLOPT_TCP_KEEPALIVE, 1L);
    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); //verbose output activated
    struct curl_slist *headers=NULL;
    headers = curl_slist_append(headers, "Content-Type: application/json");  // type JSON
    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);

    // Perform the request, res will get the return code 
    res = curl_easy_perform(curl);

    // Check for errors 
    if(res != CURLE_OK)
        fprintf(stderr, "curl_easy_perform() failed: %s\n",
                curl_easy_strerror(res));

    // cleanup
    curl_slist_free_all(headers);
    curl_easy_cleanup(curl);
}
curl_global_cleanup();

Answer 1

is Answered by Daniel Stenberg here, which is a similar/the same question.

Re-use the same curl handle in subsequent requests! Don't call curl_easy_cleanup(curl) and curl_easy_init() again between them.

So the Solution is to call curl_easy_cleanup(curl) and curl_easy_init() only once.