Encoding to utf8

gistfile1.txt

#!/usr/bin/env perl

use strict;
use warnings;
use utf8;
use File::Slurp;
use Encode;

for my $file (<*.cpp>) {
    my $data = read_file($file);
    # Already UTF-8
    next if utf8::is_utf8($data);

    # else assume ANSI code page
    $data = "\xEF\xBB\xBF".encode("utf-8", decode("cp949", $data));
    write_file($file, {binmode => ':utf8'}, $data);
}