#!/usr/bin/perl
use 5.008;
use strict;
use warnings;
use threads;
use threads::shared;
use Data::Dumper;

my %p1 :shared;
my %p2 :shared;

%p1 = (path => shift);
%p2 = (path => shift);

my @t;
push @t, threads->create(\&get_md5sums, \%p1);
push @t, threads->create(\&get_md5sums, \%p2);
$t[0]->join;
$t[1]->join;

print Dumper \%p1, \%p2;

sub doit_local {
  local $_ = shift;
  s/'/'\''/g;
  return $_;
}

sub doit_my {
  my $x = shift;
  $x =~ s/'/'\''/g;
  return $x;
}

sub get_md5sums {
  my $x = shift;
  print Dumper [$x, $$x{path}];
  $$x{foo} = join " ", map '"'.doit_local($_).'"', 'find', $$x{path}, qw/-type f -exec md5sum {} ;/;
  return 1;
}