Short answer:
foreach my $key (keys %{$matches->{$pid}}) {

Long answer:
You can think of $matches->{$pid} as the name of your hash. So now that you have the name, you put the hash symbol (%) in front and wrap it in curly braces to disambiguate, and you're all set.

elusion : http://matt.diephouse.com

In reply to Re: keys of hash of reference to hash by elusion
in thread keys of hash of reference to hash by melguin

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