[c++]recv chat packet problem

int WINAPI RecvHook(int size, char* pDestBuf)
{
      TPacketHeader* header = reinterpret_cast<TPacketHeader*>((unsigned char*)*pDestBuf);
      if (header==4)
      {
		TPacketGCChat* kChat = reinterpret_cast<TPacketGCChat*>(pDestBuf);
                char buf[1024 + 1];
                uChatSize = kChat->size - sizeof(kChat);
		buf[uChatSize]='\0';
                strncpy(buf, pDestBuf + sizeof(TPacketGCChat), uChatSize);
                cout << buf << endl;
      }
      return oldRecv(size, pDestBuf);
}