// Create a class that inherits CkHttpProgress and override desired methods..
class MyHttpProgress : public CkHttpProgress
    {
    public:
	MyHttpProgress(void) { }
	virtual ~MyHttpProgress(void) { }

	// Periodically called according to the HeartbeatMs property setting.
	// Any callback method with a "bool *abort" argument provides the opportunity to abort the current method call.
	void AbortCheck(bool *abort) 
	    { 
	    // If your application wishes to abort, set *abort = true before returning.
	    *abort = false;	    
	    }

	void PercentDone(int pctDone, bool *abort) 
	    { 
	    *abort = false;
	    }

    };

// Setting up and using the progress (callback) class..
void test(void)
{
    CkHttp http;

    MyHttpProgress myProgress;
    http.put_EventCallbackObject(&myProgress);

    // Make an AbortCheck callback every 100 milliseconds.
    // Our application can choose to abort the download in the AbortCheck callback.
    http.put_HeartbeatMs(100);

    bool success = http.Download("https://example.com/something_large.zip","c:/someDir/something_large.zip");
    if (!success)
	{
	// ....

	}

    // ....
    // ....

};