lost of more into on how to tweak some headers

    /* Now specify we want to POST data */

    curl_easy_setopt(curl, CURLOPT_POST, TRUE);

    /* Set the expected POST size */

    curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, pooh.sizeleft);

    /* we want to use our own read function */

    curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);

    /* get verbose debug output please */

    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);

    /*

      If you use POST to a HTTP 1.1 server, you can send data without knowing

      the size before starting the POST if you use chunked encoding. You

      enable this by adding a header like "Transfer-Encoding: chunked" with

      CURLOPT_HTTPHEADER. With HTTP 1.0 or without chunked transfer, you must

      specify the size in the request.

    */

#ifdef USE_CHUNKED

    {

      curl_slist *chunk = NULL;

      chunk = curl_slist_append(chunk, "Transfer-Encoding: chunked");

      res = curl_easy_setopt(curl, CURLOPT_HTTPHEADER);

      /* use curl_slist_free_all() after the *perform() call to free this

         list again */

    }

#else

    /* Set the expected POST size. If you want to POST large amounts of data,

       consider CURLOPT_POSTFIELDSIZE_LARGE */

    curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, pooh.sizeleft);

#endif

#ifdef DISABLE_EXPECT

    /*

      Using POST with HTTP 1.1 implies the use of a "Expect: 100-continue"

      header.  You can disable this header with CURLOPT_HTTPHEADER as usual.

      NOTE: if you want chunked transfer too, you need to combine these two

      since you can only set one list of headers with CURLOPT_HTTPHEADER. */

    /* A less good option would be to enforce HTTP 1.0, but that might also

       have other implications. */

    {

      curl_slist *chunk = NULL;

      chunk = curl_slist_append(chunk, "Expect:");

      res = curl_easy_setopt(curl, CURLOPT_HTTPHEADER);

      /* use curl_slist_free_all() after the *perform() call to free this

         list again */

    }

#endif

    /* Perform the request, res will get the return code */

    res = curl_easy_perform(curl);