c++ - 如何正确关闭为使用 IOCP 创建的工作线程

Question

这是Microsoft Windows 网络编程 的代码片段:

...
// Determine how many processors are on the system.
GetSystemInfo(&SystemInfo);

// Create worker threads based on the number of
// processors available on the system. For this
// simple case, we create one worker thread for each
// processor.

for (int i = 0; i < SystemInfo.dwNumberOfProcessors; i++)
{
    // Create a server worker thread, and pass the
    // completion port to the thread. NOTE: the
    // ServerWorkerThread procedure is not defined
    // in this listing.

    HANDLE ThreadHandle = CreateThread(NULL, 0, ServerWorkerThread, CompletionPort, 0, NULL);

    // Close the thread handle
    CloseHandle(ThreadHandle);
}
...

我不明白的是为什么示例会立即关闭线程句柄。是否没有必要存储它们(例如在 std::vector 中)以便您稍后可以在退出程序时终止所有工作线程？

Answer 1

没有必要。来自 msdn on CloseHandle :

Closing a thread handle does not terminate the associated thread or remove the thread object. Closing a process handle does not terminate the associated process or remove the process object. To remove a thread object, you must terminate the thread, then close all handles to the thread. For more information, see Terminating a Thread. To remove a process object, you must terminate the process, then close all handles to the process. For more information, see Terminating a Process.

在实践中，自包含线程通常在其句柄立即关闭的情况下创建，这允许在线程退出时释放资源。