gistfile1.txt

#include <windows.h>
#include <stdio.h>

static LRESULT CALLBACK test_proc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    switch (msg)
    {
        case WM_DESTROY:
            PostQuitMessage(0);
            break;
        case WM_GETICON:
            printf("WM_GETICON wParam %lu.\n", wParam);
            break;
    }
    return DefWindowProcA(hwnd, msg, wParam, lParam);
}

static HWND hwnd;

static DWORD WINAPI thread_proc(void *dummy)
{
    printf("Thread start.\n");
    UpdateLayeredWindow( hwnd, NULL, NULL, NULL, NULL, NULL, 0, NULL, ULW_OPAQUE);
    printf("Thread done.\n");
    return 0;
}

int main(int argc, char *argv[])
{
    WNDCLASSA clsA;
    HANDLE thread;
    HICON res;
    MSG msg;

    memset(&clsA, 0, sizeof(clsA));
    clsA.style = 0;
    clsA.lpfnWndProc = test_proc;
    clsA.cbClsExtra = 0;
    clsA.cbWndExtra = 0;
    clsA.hInstance = GetModuleHandleA(NULL);
    clsA.hIcon = 0;
    clsA.hCursor = 0;
    clsA.hbrBackground = GetStockObject(WHITE_BRUSH);
    clsA.lpszMenuName = NULL;
    clsA.lpszClassName = "test_class";
    RegisterClassA(&clsA);

    hwnd = CreateWindowExA(WS_EX_APPWINDOW | WS_EX_LAYERED, "test_class",
                               "Test",
                               WS_OVERLAPPEDWINDOW,
                               100, 100, 200, 200,
                               NULL, NULL, GetModuleHandleA(NULL), NULL);
    res = (HICON)SendMessageA( hwnd, WM_SETICON, ICON_BIG, 0xdeadbeef );
    printf("res %p.\n", res);
    SendMessageA( hwnd, WM_SETICON, ICON_SMALL, 0xdeadbeef );
    ShowWindow(hwnd, SW_SHOW);

    while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
        DispatchMessage(&msg);
    thread = CreateThread(NULL, 0, thread_proc, NULL, 0, NULL);
    if (WaitForSingleObject(thread, 3000) == WAIT_TIMEOUT)
        puts("Deadlock.\n");
    else
        puts("OK.\n");
    return 0;
}