Parse.com REST API with cURL and C++

I have a raspberry pi that is running a c++ program. It now needs to talk to the Parse.com cloud so it seems the REST API is the best choice. I've been programming for a year and have truly hit a wall here.

EDIT: I've been able to get the code below to run. It successfully posts "south" in a new row under the "direction" column. I had to link my compiler to -lcurl.

My remaining question is how can I in this syntax add conditions to the query? For me the limiting query is WHERE hardwareType = 2.

I can also GET all the results of my parse table if I comment out the CURLOPT_POSTFIELDS line inside curl_easy_init. How can I limit this request with the same query quoted above?

#include <iostream>
#include <curl/curl.h>
#include <string>
#include <sstream>
#include <stdexcept>

using namespace std;

int main()
{
    CURL *curl;
    CURLcode res;

    struct curl_slist *headerlist=NULL;

    headerlist = curl_slist_append( headerlist, "X-Parse-Application-Id: aaaaaaaaaaa");
    headerlist = curl_slist_append( headerlist, "X-Parse-REST-API-Key: bbbbbbbbbbbbbbbb");
    headerlist = curl_slist_append( headerlist, "Content-Type: application/json");
    //headerlist = curl_slist_append(headerlist, "-d '{"direction":"south"}'");

    curl = curl_easy_init();
    if(curl)
    {
        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);
        curl_easy_setopt(curl, CURLOPT_URL, "https://api.parse.com/1/classes/testing");
        curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "{\"direction\" : \"south\"}");

        res = curl_easy_perform(curl);

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