GetQueuedCompletionStatus
GetQueuedCompletionStatus函数有个OVERLAPPED结构，很多资料上都采用不同的结构体来扩展该结构，比如有的资料定义：typedef struct _OVERLAPPEDPLUS{OVERLAPPED ol;SOCKET s, sclient;int OpCode;WSABUF wbuf;DWORD dwBytes, dwFlags;}OVERLAPPE
