我在理解 Klein 的 C++ 串行库中的示例时遇到了一些麻烦。在此页面的大约一半处,有一个名为“使用 Win32 同步对象”的部分,我无法理解。 http://www.codeproject.com/Articles/992/Serial-library-for-C
// Create a handle for the overlapped operations
HANDLE hevtOverlapped = ::CreateEvent(0,TRUE,FALSE,0);;
// Open the "STOP" handle
HANDLE hevtStop = ::CreateEvent(0,TRUE,FALSE,_T("Overlapped_Stop_Event"));
// Setup the overlapped structure
OVERLAPPED ov = {0};
ov.hEvent = hevtOverlapped;
// Wait for an event
serial.WaitEvent(&ov);
// Setup array of handles in which we are interested
HANDLE ahWait[2];
ahWait[0] = hevtOverlapped;
ahWait[1] = hevtStop;
// Wait until something happens
switch (::WaitForMultipleObjects(2,ahWait,FALSE,INFINITE))
{
case WAIT_OBJECT_0:
// Serial port event occurred
...
case WAIT_OBJECT_0+1:
// Stop event raised
...
}
这是 WaitEvent 从该调用中执行的内容(没有所有检查和内容):
// Wait for the COM event
::WaitCommEvent(m_hFile,LPDWORD(&m_eEvent),lpOverlapped);
::SetEvent(lpOverlapped->hEvent);
两个问题: 1) 为什么他同时使用串行类中的 WaitEvent 方法,然后立即使用 Windows API 中的 WaitForMultipleObjects?它们似乎都在做同样的事情:等待 COM 端口发生某些事情。2) Stop 事件如何发出信号?WaitForMultipleObjects 是否通过名称或其他方式识别它?