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

#include <windows.h>

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

int main(void)
{
    HWND hWnd;  MSG msg;  WNDCLASS wc = { 0 };

    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = WndProc;
    wc.hCursor = LoadCursor(0, IDC_ARROW);
    wc.hbrBackground = GetStockObject(WHITE_BRUSH);
    wc.lpszClassName = "class name";
    if (!RegisterClass(&wc)) return FALSE;

    hWnd = CreateWindow(wc.lpszClassName, "window name", WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
        0, 0, 0, 0);
    ShowWindow(hWnd, SW_SHOWDEFAULT);
    UpdateWindow(hWnd);

    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wp, LPARAM lp)
{
    switch (msg) {
    case WM_DESTROY: PostQuitMessage(0); break;
    default: return (DefWindowProc(hWnd, msg, wp, lp));
    }
    return 0;
}