In addition to dragonchild's teachings,

open NEW, "> $new" or die "Cannot open $new for writing: $!";
       +  #WHAT IS THE + DOING?
[download]

The '+' is an artifact of perlmonks line-wrapping. If you look at the page you pasted from, you'll see the '+' is in red. Just remove it, it's not part of the script. The 'd/l code' link will prevent that, though you may need to remove "\r"'s from the download.

.

After Compline,
Zaxo