code: func (a *ACL) Valid() error {
  	acl_valid, err := getSymbolPointer(a.lib.handle, "acl_valid")
  	if err != nil {
  		return err
  	}
  
  	ret, err := C.my_acl_valid(acl_valid, a.a)
  	if ret < 0 {
  		return errwrap.Wrap(errors.New("invalid acl"), err)
  	}
  	return nil
  }
docs: // Valid checks whether the ACL is valid.