#!/usr/bin/perl -l

# http://perlmonks.org/?node_id=1170310

use strict;
use warnings;

while(<DATA>)
  {
  /.*(_.*_.*)/ and print $1;
  }

__DATA__
XYX_WT_7_25h_Trimmed_75.SAM
some_other_name
bad_name
one_two_three_four_five_six
[download]