to print to a file instead of printing at the screen, we just have to change:

say $text;
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to:

print $OUT_FILE $text;
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Well, that's ignoring the most important distinction between say and print: that say adds a newline at the end. And you can add a filehandle argument to say. So you'd better do:

say $OUT_FILE $text;
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If you set

$OUT_FILE = \*STDOUT;
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or even

$OUT_FILE = select;
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then you don't even have to swap code out code.

As far as your problem concerns: look at Perl I/O Layers, in particular the :utf8 and :encoding layers.