Perhaps even...

if ($needs_binmode) {
    $CGI::DefaultClass->binmode(main::STDOUT)
        unless ( -t main::STDOUT );
    $CGI::DefaultClass->binmode(main::STDIN)
        unless ( -t main::STDIN );
    $CGI::DefaultClass->binmode(main::STDERR)
        unless ( -t main::STDERR );
}
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?