If tainting was employed, it defeats the purpose of using the shorthand notation in the first place.
Why? If you're using a simple -n/-p one-liner from the CLI, you can still do that with -T. Your one-liner will still run fine, except for the one time that you do have a filename ending with '|' (or starting with '<', '>' or '|'). I assume you don't have the habit of using such filenames all the time.
This cannot be anticipated by the perl program. Perl gets @ARGV as it is from the executing shell because the shell has already done the expansion.
Yes, but it can be anticipated by the person running the program.
I mean, bad filenames may be created unintentionally by some other program working in tandem with perl's <ARGV>.
Which means, the environment is untrusted. That really isn't any different from: 
    while (<STDIN>) {  # No magic open
        chomp;
        unlink or die;
    }

[download]
if the input is created by a program that unintentionally produces a name of an important file, you also have a problem. Again, a problem that could have been prevented by checking the data you got from the outside (and enabling tainting means Perl checks whether you've checked).

In reply to Re^7: magic-diamond <> behavior -- WHAT?! by JavaFan
in thread magic-diamond <> behavior -- WHAT?! by repellent

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