How to know Buffer.toString() consumed how many bytes?

[heroboy]

Now I need to call Buffer.length - Buffer.byteLength(str). It looks like not efficient.
And it makes hard to correctly convert chunks to string in TransformStream.

[bnoordhuis]

I think you answered your own question? If you're doing partial writes, use a require('string_decoder').StringDecoder.

Can you direct support questions to SO or help next time? Thanks.

[heroboy]

Sorry. Because I didn't find a similar link in page: https://nodejs.org/en/get-involved/