code: func (container *Container) FromDisk() error {
  	pth, err := container.ConfigPath()
  	if err != nil {
  		return err
  	}
  
  	jsonSource, err := os.Open(pth)
  	if err != nil {
  		return err
  	}
  	defer jsonSource.Close()
  
  	dec := json.NewDecoder(jsonSource)
  
  	// Load container settings
  	if err := dec.Decode(container); err != nil {
  		return err
  	}
  
  	// Ensure the operating system is set if blank. Assume it is the OS of the
  	// host OS if not, to ensure containers created before multiple-OS
  	// support are migrated
  	if container.OS == "" {
  		container.OS = runtime.GOOS
  	}
  
  	return container.readHostConfig()
  }
docs: // FromDisk loads the container configuration stored in the host.