It used to be more of a problem before 3-arg open (and you are only using two args, so it is a problem). When you include "|" as the first or last character of a "file name", perl interprets the "file" as a command to run. That's why -T makes your program safer. Even though you could allow "|" in your file name, it forces you think about such things.

In reply to Re^6: Insecure dependency in open while running with -T switch by runrig
in thread Insecure dependency in open while running with -T switch by vit

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