I just noticed your SO has some answers. Perhaps those give you the info you need and what follows is redundant but maybe not, and I'd already written this, so:

ETA: This bit from Sinan's post:

We don't do any such translation when using .encode/.decode, and of course when reading/writing Bufs to files, providing an escape hatch from translation if needed.

reads to me like a very direct claim that there's a way to read and write files without translating newlines.

Hth.

perl6.party (not mine)

In reply to Re^3: Perl6: Capturing newline in a string by raiph
in thread Perl6: Capturing newline in a string by stevieb

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