#!/usr/bin/perl
use strict;
use warnings;
use Encode::Guess;

undef $/;  # slurp on

my $dir = '.';
if (@ARGV > 0) {
  $dir = $ARGV[0];
}

opendir DIR, $dir or die "Can't opendir '.': $!\n";
my @files = grep /\.csv$/i, readdir(DIR);
closedir DIR;

Encode::Guess->add_suspects(qw(latin1 cp1252)); # What else?
foreach my $file (@files) {
  open my $fh, "<:raw", "$dir/$file"
    or die "Can't open $!\n";
  my $data = <$fh>;
  close $fh;

  my $enc = guess_encoding($data);
  if (ref $enc) {
    print "$file: " . $enc->name . "\n";
  } else {
    print "Didn't work for: $file\n";
  }
}

exit;