private boolean isEnabled(int i) {
            switch (i) {
                case SUPGA:
                    return DO_SUPGA;
                case ECHO:
                    return DO_ECHO;
                case NAWS:
                    return DO_NAWS;
                case TTYPE:
                    return DO_TTYPE;
                case LINEMODE:
                    return DO_LINEMODE;
                case NEWENV:
                    return DO_NEWENV;
                default:
                    return false;
            }
        }// isEnabled