func Set(key, value string) error {
	err := _Set(_SETTINGS.user, key, value)
	if err != nil {
		return err
	}

	if _SETTINGS.useKDE {
		return _Set(_SETTINGS.kde, key, value)
	}
	return nil
}
func Set(key, value string) error {
	err := _Set(_SETTINGS.user, key, value)
	if err != nil {
		return err
	}

	if _SETTINGS.useKDE {
		return _Set(_SETTINGS.kde, key, value)
	}
	return nil
}
// == Set session-wide variables
// Set sets the value of the environment variable named by the key that
// affects the current user.
// It returns an error, if any.