Win32 API：如何读取序列号，或者如果不是数据则在超时内退出

我需要一个函数来从串行端口读取数据，或者如果在时间间隔内没有数据则返回。例如。在 GNU/Linux 上你可以使用poll()orselect()+read()。 Windows 中有类似的东西吗？

下面是我尝试过的：它应该可以工作，但是功能获取重叠结果() http://msdn.microsoft.com/ru-ru/library/windows/desktop/ms683209(v=vs.85).aspx要么有问题，要么没有很好的文档记录；它没有报告任何内容，而不是读取的字节数（甚至不是零，例如，如果我不初始化lpNumberOfBytesTransferred参数，它只是包含垃圾）.

// NOTE: the `file` should be opened in non-blocking mode
long ReadData(HANDLE file, char* buf, long szbuf, int msTimeout){
    OVERLAPPED ReadState = {0};
    ReadState.hEvent = CreateEvent(0, true, false, "☠");
    if (!ReadState.hEvent){
        PrintLastErr();
        return -1;
    }
    unsigned long BytesRead = 0; //number of bytes was read
    if (!ReadFile(file, buf, szbuf, &BytesRead, &ReadState)){
        // This creates a reading event. Below we wait for it to complete, and cancel on timeout
        if (GetLastError() != ERROR_IO_PENDING){
            PrintLastErr();
            return -1;
        }
        // No, I can't use WaitForSingleObject(), it exits with disregard to whether
        // reading is ongoing or no more data left (e.g. in case of a serial port).
        while(1) {
            std::this_thread::sleep_for(std::chrono::milliseconds( msTimeout ));
            unsigned long ret;
            puts("Getting result");
            if (!GetOverlappedResult(file, &ReadState, &ret, false)
                && GetLastError() != ERROR_IO_INCOMPLETE){
                PrintLastErr();
                return -1;
            }
            printf("result is %lu\n",ret);
            if(ret == BytesRead){
                return BytesRead;
            }
            BytesRead = ret;
        }
    } else { //completed immediately
        printf("Bytes read %i\n");
        assert(BytesRead <= LONG_MAX);
        return (long)BytesRead;
    }
}

打开 COM 端口后调用 SetCommTimeouts。如果没有收到数据，这会将 ReadFile 设置为在一段时间间隔后返回。然后你只需调用 ReadFile 即可。不需要重叠或事件或 GetOverlappedResult。