Please don't take this wrong. Perhaps you've moved on and done what I'll say below, but I don't know, and I have to assume you have not.
You'll note that I added a note to my original encouraging the use of the code marto posted first, over mine. In addition, I encouraged you to read the actual documentation for the class, which would have shown you where the ls -la bit comes from. And, I pointed out in the comment, and the code, that this is for Unix-like systems, which, based upon the error message you reported, you are not trying to FTP to.
We are happy to help, and code snippets have been provided. Have you tried the code samples marto pointed you to? If my code does not work, the code from the modules' development team is much more likely to. And if it does not, please give us more data, as mentioned in How do I post a question effectively? and Perlmonks FAQ.
Why? Because we've here to help, and it's best if you help us help you. Those documents will tell you how, and how to give info like the Operating Systems, which might just be your main issue. But I don't know that, and thus cannot help you resolve the issue.
Bottom line: I CANNOT debug your error properly without you testing the other code sample, and providing more complete details about you goals. OK?
----Asim, known to some as Woodrow.
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