Передача данных с одного приложения в другое

#include <windows.h>
#include <stdio.h>
#include <string.h>
#define UNICODE
char Buf[100];
PCOPYDATASTRUCT pMyCDS;
RECT rect;
static char szAppName[] = "MyWindowApp";
static char szWinCaption[] = "MessageReceiver";
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
    HWND hwnd;
    MSG msg;
    WNDCLASSEX wndclass;
    wndclass.cbSize = sizeof(wndclass);
    wndclass.style = CS_HREDRAW | CS_VREDRAW;
    wndclass.lpfnWndProc = WndProc;
    wndclass.cbClsExtra = 0;
    wndclass.cbWndExtra = 0;
    wndclass.hInstance = hInstance;
    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
    wndclass.hbrBackground = (HBRUSH)GetStockObject(COLOR_BACKGROUND);
    wndclass.lpszMenuName = NULL;
    wndclass.lpszClassName = szAppName;
    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
    RegisterClassEx(&wndclass);
    hwnd = CreateWindow(szAppName, szWinCaption, WS_OVERLAPPEDWINDOW, GetSystemMetrics(SM_CXFULLSCREEN) / 2 - 170, GetSystemMetrics(SM_CYFULLSCREEN) / 2 - 100, 340, 200, NULL, NULL, hInstance, NULL);
    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam) {
 
    HDC hdc;
    PAINTSTRUCT ps;
    switch (iMsg)
    {
    case WM_CREATE:
        return 0;
        break;
        //break;
    case WM_COPYDATA:   //прийом повідомлення
       pMyCDS = (PCOPYDATASTRUCT)lParam;
        strcpy_s(Buf, (char *)pMyCDS->lpData);
        Buf[pMyCDS->cbData] = 0;
        if (!strcmp(Buf, "quit"))
            SendMessage(hwnd, WM_DESTROY, 0, 0);
        InvalidateRect(hwnd, NULL, 0);
        break;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        GetClientRect(hwnd, &rect);
        DrawText(hdc, Buf, -1, &rect, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
        EndPaint(hwnd, &ps);
        return 0;
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hwnd, iMsg, wParam, lParam);
}