... when I execute the perl codes on my computer, it returns the whole text back.

What Perl codes? Not because I doubted kcott but just to be able to say I did so, I copied out the code of the OP and only added the use statements kcott did, and I got the same output without warnings or errors. Are you saying that you can do the same and get a different output? If so, how does it differ? (It's not enough just to say "It's not what I want.")

Offhand, I cannot think of any environmental variable or OS peculiarity that would cause the originally posted code to differ in its behavior. We need more info about this.