Your first example, with

@returned_files = match_files(\@array, \%hash);
[download]

looks like it should work.

Also, to dereference an array reference, try @$returned_files

Compare these examples. The first returns a reference to an array:

#!/usr/bin/perl -w

use strict;

sub ret_array
{
    my @array = qw( 1 2 3 4 5 );
    return \@array;
}

my $returned_array = ret_array();
print @$returned_array;
[download]

And this returns an array

#!/usr/bin/perl -w

use strict;

sub ret_array
{
    my @array = qw( 1 2 3 4 5 );
    return @array;
}

my @returned_array = ret_array();
print @returned_array;
[download]