Usually a negative number returned e.g., -1 is bad, no good, not reliable.
and a positive number is good, continue with confidence.

So I still can't relate -1 as being "CONNECTED OK" to my original comment.
Maybe -1 in this case means the FTP server connection is "not reliable" but my script code forces the server to bow to my command - "PORT" mode.

(Mike Cole) I saw your name down below so I clicked your box.