undef$/;print<>^<>

One the the  <> readlines will read all of the data from all of the files on the command line and the other will return undef so you are xoring everything with nothing leaving the text unchanged.

Update: OK. I missed the scalar context. I was wrong.

In reply to Re: encryption golf (one time pad) by jwkrahn
in thread encryption golf (one time pad) by mr_mischief

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