#include "callout.h"

LoadLibrary("callout.dll");
HWND hwndCallout = CreateWindow(CALLOUT_CLASS,
                    "Guess what this icon does...",
                    WS_POPUP, 0, 0, 0, 0,
                    NULL, 0, hInstance, NULL);
Callout_SetAnchor(hwndCallout, 100, 200);
Callout_SetBorder(hwnd, 2, TRUE);
ShowWindow(hwndCallout, SW_SHOW);

Example 2: Using wrapper macros.