source: Daodan/src/guitest.c@ 1007

#include <windows.h>

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

void guitest(HMODULE hInstance, int nCmdShow)
{
        MSG  msg;    
        HWND hwnd;
        WNDCLASSW wc;

        wc.style         = CS_HREDRAW | CS_VREDRAW;
        wc.cbClsExtra    = 0;
        wc.cbWndExtra    = 0;
        wc.lpszClassName = L"Window";
        wc.hInstance     = hInstance;
        wc.hbrBackground = GetSysColorBrush(COLOR_3DFACE);
        wc.lpszMenuName  = NULL;
        wc.lpfnWndProc   = WndProc;
        wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
        wc.hIcon         = LoadIcon(NULL, IDI_APPLICATION);

        RegisterClassW(&wc);
        hwnd = CreateWindowW( wc.lpszClassName, L"Window",
                WS_OVERLAPPEDWINDOW | WS_VISIBLE,
                100, 100, 350, 250, NULL, NULL, hInstance, NULL);  

        ShowWindow(hwnd, nCmdShow);
        UpdateWindow(hwnd);

        while( GetMessage(&msg, NULL, 0, 0)) {
                DispatchMessage(&msg);
        }
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
        switch(msg)
        {
                case WM_DESTROY:
                        PostQuitMessage(0);
                        return 0;      
        }

        return DefWindowProcW(hwnd, msg, wParam, lParam);
}