ARRAY(x15d505c) is telling you that you're printing an array reference. You really want to print the array, and to do that you dereference the array ref.

print "@{$link{testing}}\n";
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This solution works because @{....} dereferences the array-ref held in $link{testing}. Oh, and I wrapped it in double-quotes to take advantage of the fact that by default, lists (or arrays) interpolated in double quotes result in each element being interpolated into the string with a space between each element. Visually, it works out nicely usually. You can alter that behavior by tinkering with the Perl special variable $".

By the way, if all you're trying to do is find a quick-n-dirty way to reliably print out the contents of %link, you can use Data::Dumper.

use Data::Dumper;
# your code goes here...
# Now we'll print the results:
print Dumper \%link;
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