While this can be done in Perl (see, for example crypt), this is not entirely a Perl question, at least the way you've phrased it.

So, is this a programming exercise? If so, there are many encryption/decryption algorithms. Probably the easiest is xor-ing the plain text, character by character, with a key. There are also transposition ciphers, which scramble word order according to a key.

If this isn't an exercise, you could try gpg, presuming it's legal for you to download and use it. There's also an associated Perl module, gpg.

emc

Insisting on perfect safety is for people who don't have the balls to live in the real world.

—Mary Shafer, NASA Dryden Flight Research Center

In reply to Re: file encryption by swampyankee
in thread file encryption by shashi2713

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