code: func validateReadonlyRootfs(hc *container.HostConfig) error {
  	// We may not be passed a host config, such as in the case of docker commit
  	if hc == nil {
  		return nil
  	}
  	if hc.ReadonlyRootfs {
  		return fmt.Errorf("Windows does not support root filesystem in read-only mode")
  	}
  	return nil
  }
docs: // validateReadonlyRootfs performs platform specific validation of the ReadonlyRootfs setting