#!/usr/bin/perl
while (<>) {
    chomp;
    $c{$_}++ for (split //);
}
printf("%02x : %s : %d\n",ord($_),$_,$c{$_}) for(sort keys %c);

##</code><code>##

  perl  that_script < your_file.txt > char_list.txt

##</code><code>##

   perl unichist -x < your_file.txt > char_list.txt