how to get the PID of process which is triggering a mouse event in another process - events

Question

I have 2 C++ applications, mouseEventCapture and mouseEventTrigger. The job of mouseEventTrigger is to trigger an mouse event and the job of mouseEventCapture is to capture all the mouse activities.
My mouseEventCapture is capturing the mouse events triggered by mouseEventTrigger.
Now the next step in my mouseEventCapture is to capture the pid of the process which is triggering the mouse event(ie I need to capture the PID of mouseEventTrigger in my mouseEventCapture application).
I'm unable to figure out how this can be done in C++. Can anyone please help me out with this?
mouseEventTrigger.cpp
#include <Windows.h>
int main()
{
int x = 3; int y = 4;
SetCursorPos(x, y); //set cursor position
mouse_event(MOUSEEVENTF_MOVE, x, y, 0, 0);
return 0;
}
mouseEventCapture.cpp
#include <iostream>
#include <Windows.h>
HINSTANCE hInst = NULL;
DWORD dwThreadId = 0;
HWND hwnd = NULL;
LRESULT CALLBACK MouseHook(int nCode, WPARAM wParam, LPARAM lParam)
{
switch (wParam)
{
case WM_MOUSEMOVE:
case WM_SETCURSOR:
std::cout << "Mouse moved !!" << " " << point.x << " " << point.y << std::endl ;
break;
case WM_LBUTTONDOWN:
case WM_LBUTTONUP:
std::cout << "Mouse left button clicked !!" << std::endl;
break;
case WM_RBUTTONDOWN:
case WM_RBUTTONUP:
std::cout << "Mouse right button clicked !!" << std::endl;
break;
default:
break;
}
return CallNextHookEx(NULL, nCode, wParam, lParam);
}
int main()
{
std::cout << "Tracking mouse move!\n";
HHOOK mouse = SetWindowsHookEx(WH_MOUSE_LL, &MouseHook, hInst, dwThreadId);
MSG message;
while (GetMessage(&message, hwnd, NULL, NULL) > 0)
{
TranslateMessage(&message);
DispatchMessage(&message);
}
UnhookWindowsHookEx(mouse);
return 0;
}