in reply to Closing Perl Source
I know I'm repeating some of what's been said by some of the other's here. But seriously - why do you want to close it up?
If you're afraid people will copy it, they can still copy a binary. Just use a copyright notice as someone else mentioned.
If you're afraid that people will steal your brilliant idea - if it's so brilliant that people will want to steal it, you'll need more than obfuscation, you'll need a patent, apply for one.
What's your motivation?
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