outlasterror

 void outLastError(const char * errStr)
{
 LPTSTR messageBuf;
 FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|FORMAT_MESSAGE_FROM_SYSTEM,
  NULL,(DWORD)WSAGetLastError(),0,(LPTSTR)&messageBuf,0,NULL);
 char one[256] = {0};
 WideCharToMultiByte(CP_ACP,0,messageBuf,-1,one,256,NULL,NULL);
 cout<<errStr<<one<<endl;
 LocalFree(messageBuf);
}