Oppps! I didn't even realize that the directory gets reset when the program exits. All my other experience programming in the dos environment ( masm, turbo pascal ) you had to save the path and restore it when you exit or you would be left in the last directory your program set.

That solves that problem. I can remove that section of code and use taint checking.

I had looked at the Cwd module, but its implementation is the same:

Taken from Cwd.pm

sub _backtick_pwd {
    my $cwd;
    chop($cwd = `pwd`);
    $cwd;
}
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And the working directory returned is tainted.

zzspectrez