CreateNamedPipe和WaitForMultipleObjectsEx

问题描述

我有一个线程可以像这样创建一个命名管道:

I have a thread which creates a named pipe like this:

CreateNamedPipe('\\\\.\\pipe\\dirwatcher', PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED, PIPE_TYPE_BYTE, 1, 1, 1, 0, null);

然后我生成另一个名为"poller"的线程，该线程具有监视文件.我想让它等待这个管道，所以我可以中断无限轮询.

I then spawn another thread called "poller" and this one has watches files. I want to make it wait for this pipe though, so I can interrupt the infinite poll.

我在此轮询线程中创建管道，如下所示:

I create the pipe in this poller thread like this:

pipe = CreateFile('\\\\.\\pipe\\dirwatcher', GENERIC_READ, FILE_SHARE_READ, null, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, null);

然后我尝试像这样在管道上等待:

I then try to wait on this pipe like this:

在这种情况下，LP_HANDLES是一个只有一个元素pipe的数组:

For this case LP_HANDLES is an array with just one element, pipe:

rez_wait = WaitForMultipleObjectsEx(LP_HANDLES.length, LP_HANDLES, false, INFINITE, true);
console.log('rez_wait:', rez_wait);

但是，这根本没有等待，并立即返回0.在创建命名管道并连接到它的过程中，我都使用了重叠标志.有人知道如何解决这个问题吗?

However this doesn't wait at all, and immeidately return 0. I used overlapped flag in both creating the named pipe and connecting to it. Does anyone know how to fix this?

这是我的代码，它是js-ctypes:

Here is my code specifically, it is js-ctypes:

创建管道: https://github.com/Noitidart/jscFileWatcher/blob/master /DirectoryWatcherWorkerSubscript.js#L91-L99

在轮询线程中获取管道: https://github.com/Noitidart/jscFileWatcher/blob/master /DirectoryWatcherPollWorker.js#L53-L64

Getting the pipe in poller thread:https://github.com/Noitidart/jscFileWatcher/blob/master/DirectoryWatcherPollWorker.js#L53-L64

在管道上等待: https://github.com/Noitidart/jscFileWatcher/blob/master/DirectoryWatcherPollWorker .js#L89

谢谢

推荐答案

您不能使用 WaitForMultipleObjectsEx ，如备注所述:

You cannot wait for pipes using WaitForMultipleObjectsEx as stated within the remarks:

• 更改通知
• 控制台输入
• 事件
• 内存资源通知
• Mutex
• 过程
• 信号量
• 线程
• 等待计时器

• Change notification
• Console input
• Event
• Memory resource notification
• Mutex
• Process
• Semaphore
• Thread
• Waitable timer

您必须使用 PeekNamedPipe 来完成这项工作(如果管道为空，它不会等待)，或者您只需在管道上执行阻塞ReadFile即可.

前段时间我遇到了相同的问题，我通过等待WaitForSingleObject事件来解决该问题，如果我在管道中放了东西，我会设置该事件.我必须这样做，因为我有多个管道，并且只有一个由事件唤醒的读取器线程"，并且使用PeekNamedPipe来检查哪个管道包含数据(并且我不想创建多个读取器线程"在ReadFile调用中被屏蔽).

I've encountered the same problem a while ago and I've solved it by waiting for an event with WaitForSingleObject which I set if I've put something into the pipe. I had to do this since I had several pipes and only one "reader thread" which woke up by the event and the used PeekNamedPipe to check which pipe contains data (and I didn't want to create several "reader threads" which are blocked within a ReadFile call).

无论如何，对于我来说，您可以使用WaitForMultipleObjects等待几乎所有内容，这很奇怪，除了管道(这非常令人讨厌！).

Anyway to me it is quite strange that you can wait for almost anything using WaitForMultipleObjects except pipes (which is very annoying!).

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