m/00(\d{3})\.000(\d\d).00(\d{3})\.0000.0000/
  and print "$1$2$3";

#!/usr/bin/perl

use strict;
use warnings;

my $string = "00XXX.000XX.00XXX.0000.0000";

$string =~ tr/0.//d;

print $string;

my $test = @$ref[3];
$test =~ m/00(\d{3})\.000(\d\d).00(\d{3})\.00000.00000 /;
print $test."\n";

m/00(\d{3})\.000(\d\d)\.00(\d{3})\.0000\.0000/
 and print "$1$2$3";

my $input = '00117.00031.00846.00000.00000';
my @fetch = $input =~ m/00(\d\d\d)\.000(\d\d)\.00(\d\d\d)\.00000\.00000/;
my $res   = join "", @fetch;
print "$res\n";