Beep when done

[tenhobi]

Hi, I want to make voice control for build. I wrote something like this below, but it is not working.
Does anybody know how to fix it? :)

It throws this error - http://prntscr.com/6lxpzu

// Compile Sass, autoprefix properties, generate CSS.
gulp.task('sass', function () {
    return sass('src/sass/style.scss', {style: 'compressed'})
        .pipe(autoprefixer())
        .pipe(rename('style.css'))
        .pipe(gulp.dest('src/css/'))
        .pipe(gutil.beep()); // beep when build is done
});

[sindresorhus]

Support questions are better asked on StackOverflow:
http://stackoverflow.com/questions/tagged/gulp
Paste in the link to the question here so others can follow ;)

[tenhobi]

My question on stackoverflow - http://stackoverflow.com/questions/29300726/gulp-beep-when-done