#!/usr/bin/perl
use warnings;
use strict;
use Fcntl ':flock';

my $path = 'c:/perl/dvd_files/';

# only doing the problem files - those with unchanged names
my @files = glob "$path*.txt"; 

for (@files) {
    local $/;
    open my $fh, '+<', $_ or warn($!), next;
    flock $fh, LOCK_EX;
    binmode $fh;
    my $text = <$fh>;

##</code><code>##

    $text =~ tr/0-9{}//d;
    seek $fh, 0, 0;
    truncate $fh, 0;
    print $fh $text;
}