(Win32) Wndproc

// ...

	// message pump
	MSG msg;
	while (GetMessage(&msg, nullptr, 0, 0) > 0)
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	return 0;
}

#include <Windows.h>

LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	switch (msg)
	{
	case WM_CLOSE:
		PostQuitMessage(69);
		break;
	}
	return DefWindowProc(hWnd, msg, wParam, lParam);
}

int CALLBACK WinMain(
	HINSTANCE hInstance,
	HINSTANCE hPrevInstance,
	LPSTR lpCmdLine,
	int nCmdShow)
{
	const auto pClassName = "hw3dbutts";
	// register window class
	// 자세한 설명은 검색 추천 ... 일단 받아들인다.
	WNDCLASSEX wc = {0};
	wc.cbSize = sizeof(wc);
	wc.style = CS_OWNDC;
	wc.lpfnWndProc = WndProc/*DefWindowProc*/;
	wc.cbClsExtra = 0;
	wc.cbWndExtra = 0;
	wc.hInstance = hInstance;
	wc.hIcon = nullptr;
	wc.hCursor = nullptr;
	wc.hbrBackground = nullptr;
	wc.lpszMenuName = nullptr;
	wc.lpszClassName = pClassName;
	wc.hIconSm = nullptr;
	RegisterClassEx(&wc);

	// create window
	// 역시 자세한 설명은 검색 추천
	HWND hWnd = CreateWindowEx(
		0, pClassName,
		"Happy Hard Window",
		WS_CAPTION | WS_MINIMIZEBOX | WS_SYSMENU,
		200, 200, 640, 480,
		nullptr, nullptr, hInstance, nullptr
		);

	ShowWindow(hWnd, SW_SHOW);

	// message pump
	MSG msg;
	BOOL gResult;
	while ((gResult = GetMessage(&msg, nullptr, 0, 0)) > 0)
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	if (gResult == -1)
	{
		return -1;
	}
	else
	{
		return msg.wParam;
	}

	return 0;
}