Thanks to all who have helped me out with this one; my first "real" program!
Code snippet: 
  foreach $element_priv(@priv) {
       open FILE, "$as_dir/$element_priv" or warn ("Can't open $as_dir
+/$element_priv: $!\n"), next;
       while ($compare_lines = <FILE>) {
           chomp $compare_lines;
           next if ($compare_lines =~ /unknown|shutdown/);
           ($as,$as_name,$neighbor,$router,$interface,$address,$interf
+ace_name,$ifindex,$vpi,$vci) = split(' ',$compare_lines);
           push @{$HoL_compare_priv{$router}}, $interface_name;
       }
   }

 my %no_priv_matches;
   
   foreach my $key (keys %HoL_compare_priv) {
       push @{$no_priv_matches{$key}}, $HoL_compare_priv{$key}
       unless exists $HoL_priv{$key};
   }


   foreach my $group (keys %no_priv_matches) {
       print "New interconnects for $group are:\n";
      foreach (@{$no_priv_matches{$group}}) {
           print "\t@{$no_priv_matches{$group}}\n";
       }
   }

[download]
When run, prints: 
New interconnects for vienna1-nbr2 are:
        ARRAY(0x1e9184)
New interconnects for crtntx1-cr8 are:
        ARRAY(0x1df388)
New interconnects for washdc3-br1 are:
        ARRAY(0x1e91e4)
New interconnects for chcgil2-cr1 are:
        ARRAY(0x207358)

[download]
How can I dereference those array references?

In reply to Dereferencing Hash of Array by Tuna

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