It's theoreticly very difficult to get right. In fact, I don't think you can do it without compiling your own version of perl.

• If perl can decrypt the code, then all the information to decrypt should be there.
• You can set breakpoints inside perl.
• -MO=Deparse will see through source filters.
• You can set environment vars to load deparse even if argv gets filtered.

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Warning: Unless otherwise stated, code is untested. Do not use without understanding. Code is posted in the hopes it is useful, but without warranty. All copyrights are relinquished into the public domain unless otherwise stated. I am not an angel. I am capable of error, and err on a fairly regular basis. If I made a mistake, please let me know (such as by replying to this node).

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