#!/usr/bin/perl

use strict;
use warnings;

use XML::Simple;

my $file = './Test.xml';
my $head = $ARGV[0] || 'Unknown';

my $map = XMLin($file, forcearray => ['header', 'act'], keyattr => { header => 'name'});

my $header = $map->{header}->{$head};

if($header) {
  foreach my $act ( @{$header->{act}} ) {
    print "act: $act\n";
  }
}
else {
  print "No match for '$head'\n";
}