c++ - FindFirstChangeNotification 锁定父文件夹

Question

我正在使用 FindFirstChangeNotification()/ReadDirectoryChangesW() 来监视文件夹的更改。它按预期工作。我的问题是:当我尝试重命名 Watched 文件夹的父级时，访问被拒绝，错误 5。我猜我的 FCN 句柄已打开文件夹以进行通知监视，并且不允许更改父级。

有什么方法可以监控子目录，比如 c:\folder\subfolder\anotherfolder\并且仍然能够打开命令提示符(或其他程序)并执行“重命名 c:\folder\c:\folder2 "

这是我的代码片段

    //
    // Sign up for notifications on the object. 
    //
    m_bWatchSubTree = TRUE;
    m_dwWatchFlags =
        FILE_NOTIFY_CHANGE_SECURITY |       // (0x100) change to security descriptor (NTFSACL?)
        FILE_NOTIFY_CHANGE_CREATION |       // (0x40) change to creation date
        FILE_NOTIFY_CHANGE_LAST_ACCESS |    // (0x20) change to last access date  
        FILE_NOTIFY_CHANGE_LAST_WRITE |     // (0x10) any change to the modification date/time of file in the folder
        FILE_NOTIFY_CHANGE_SIZE |           // (0x08) Size changed
        FILE_NOTIFY_CHANGE_ATTRIBUTES |     // (0x04) Atributes of something changed
        FILE_NOTIFY_CHANGE_DIR_NAME |       // (0x02) DIR name change in watched folder rename,create,delete FOLDER
        FILE_NOTIFY_CHANGE_FILE_NAME;       // (0x01) FILE name change in watched folder. rename,create,delete FILE

    CString strObjectPathAndName(_T("c:\\folder\\subfolder\\anotherfolder\\");
    m_hChangeHandle = ::FindFirstChangeNotification(strObjectPathAndName, m_bWatchSubTree, m_dwWatchFlags);
    if (m_hChangeHandle != INVALID_HANDLE_VALUE)
    {
        DWORD dwStatus = ::WaitForSingleObject(m_hChangeHandle, INFINITE);
        HANDLE  hDir = ::CreateFile(strObjectPathAndName, 
                                FILE_LIST_DIRECTORY,
                                FILE_SHARE_READ | FILE_SHARE_WRITE| FILE_SHARE_DELETE,
                                NULL, //security attributes
                                OPEN_EXISTING,
                                FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OVERLAPPED,          
                                NULL);
        DWORD dwBytesReturned = 0;
        FILE_NOTIFY_INFORMATION *p = (FILE_NOTIFY_INFORMATION*)nb.GetBuffer();
        if (::ReadDirectoryChangesW(hDir, p, nb.GetMaxSize(), m_bWatchSubTree, m_dwWatchFlags, &dwBytesReturned, NULL, NULL))
        {
        //
        // do some stuff
        }
    }

Answer 1

不确定这是否是你需要的，

如果您有兴趣在c:\folder\subfolder\anotherfolder\ 中保持当前监听器的同时监听另一个路径，您将需要一组HANDLE 类型.

在你的代码中它看起来像这样:

HANDLE m_hChangeHandle[x];// int x should be the quantity of your desired listeners.

当然，您需要为每个数组使用 FindFirstChangeNotification，即:

m_hChangeHandle[0] = FindFirstChangeNotification(..., ..., ...);
m_hChangeHandle[1] = FindFirstChangeNotification(..., ..., ...);
//and so on..

由于您现在使用的监听器超过 1 个，因此您不能继续使用 WaitForSingleObject，而是使用 WaitForMultipleObjects .即:

WaitForMultipleObjects(x, m_hChangeHandle, FALSE, INFINITE);//False will wait for a change in at least one of the listeners.

希望这是您需要的。