My questions: how do I know that I have to apply decoding more than once

You have to deduce that from the input yourself. There's no way perl could know it for you.

However if you have a sample of the input, the same sample correctly decoded and an idea what encodings are invovled, my module Encode::Repair can help you.

and why different utf8 decoders behave differently in perl?

Encode::decode is a high level API, and thus does extra sanity checks that the low-level API does not.

Perl 6 - second systems done right

In reply to Re: Utf8 experts help! by moritz
in thread Utf8 experts help! by chessgui

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