// dd if=/dev/urandom of=file count=10 bs=1m

var through2 = require('through2');
var fs = require('fs');

fs.createReadStream('file').pipe(slowTransform()).pipe(process.stdout);

function slowTransform() {
	return through2(function(buffer, encoding, callback) {
		var self = this;

		setTimeout(function(buffer) {
			self.push(buffer.length + '\n');
		}, 100, buffer);

		callback();
	});
}