Exposed internals. I know about the guts. I'd like to not care. KTHX.

# XXX PerlIO: Wide character...
binmode $socket, utf8::is_utf8( $data ) ? ':utf8', ':raw';
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While the status of the UTF8 flag currently needs to be known and manipulated in some situations (bad!), that's not one of them. The UTF8 flag offers no indication as to whether something needs to be encoded or not. See Re: Decoding, Encoding string, how to? (internal encoding)