#!perl -w
# usage:  perl eight2sixteen.pl INFILE OUTFILE

use strict;

my($in,$out) = @ARGV;

open(IN,$in) or die "cannot open $in $!";
open(OUT,">$out") or die "cannot open $out $!";

binmode OUT;

use utf8; # treat input as utf8 characters, not byte series.

use Unicode::String 'utf8','byteswap2', 'utf16';

# make sure the byte order mark is present.
my $firstString;
$firstString = <IN>;
if (ord($firstString) != 0xfeff) {
    # not present. Construct it and print it to OUT.
    my $bom = Unicode::String->new();
    $bom->chr(0xfeff);
    print OUT byteswap2($bom->utf16);
}

$firstString = utf8($firstString);
print OUT byteswap2($firstString->utf16);

# print all remaining lines.
while (<IN>) {
    my($u) = utf8($_);
    print OUT byteswap2($u->utf16);
}

close(IN) or die "cannot close $in $!";
close(OUT) or die "cannot close $out $!";