I think that you want to return the matched characters. 
use strict;
use warnings;
my $string = 'XXXXXXXXXXABXXXXXXXXX';
my ($match) = $string =~ m/X{10}([AB]{2})X{9}/;
print $match;

[download]

OUTPUT:

AB

UPDATE: Added Output

Bill

In reply to Re: Regex Pipe Return by BillKSmith
in thread Regex Pipe Return by TapTapTaperoo

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