As perlsec points out, internal data can be tainted without danger. However before it gets near the shell, it is important that it be validated. The entire point of taint mode is to guarantee that you don't forget to do that - ever.

In reply to Re (tilly) 3: A rumination on finding secure scripts, versus rolling-your-own by tilly
in thread A rumination on finding secure scripts, versus rolling-your-own by Hero Zzyzzx

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