code: func ReadMemInfo() (*MemInfo, error) {
  	msi := &memorystatusex{
  		dwLength: 64,
  	}
  	r1, _, _ := procGlobalMemoryStatusEx.Call(uintptr(unsafe.Pointer(msi)))
  	if r1 == 0 {
  		return &MemInfo{}, nil
  	}
  	return &MemInfo{
  		MemTotal:  int64(msi.ullTotalPhys),
  		MemFree:   int64(msi.ullAvailPhys),
  		SwapTotal: int64(msi.ullTotalPageFile),
  		SwapFree:  int64(msi.ullAvailPageFile),
  	}, nil
  }
docs: // ReadMemInfo retrieves memory statistics of the host system and returns a
  //  MemInfo type.