Hi guys, I have a program that I am trying to write for the llama. it is question 4 of chapter 9.

It asks the student to "Write a program to add a copyright line to all of your programs, so far by placing a line such as ' ## Copyright 200x (C) by Yours Truly.

Place it in the file immediately following the shebang line. You should edit the files "in place" and keep a backup. Presume that the programs should be invoked with the filenames on the command line.

here's my answer: 
#!/usr/bin/perl
use strict;
use warnings;

$^I = ".old";

while (<>) {
   if (/^#!/) {
      $_ .= " ## Copyright (C) 2008 Yours Truly\n";
   }
}

[download]
But what this code does is thankfully backup the original file, but"clobber" the contents of the file it's supposed to be editing. The output is completely blank, and I don't understand why.

Any help here would be greatly appreciated!

In reply to clobbering output by bluethundr

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