Is your linux machine going to be using smb and ms-windows-style paths with back-slashes as directory-level delimiters? I'm blissfully ignorant of smb issues, and all my linux usage assumes NFS with forward slashes -- if there's a way for perl on linux to DWIM given a literal path string like '\\level1\level2\file.name', that's news to me.

If the OP code is failing in a linux environment, I would assume that's because you're using literal back-slashes in your directory path strings, when you should be using forward slashes -- or better yet, using File::Spec so that your script can specify directory paths in an OS-agnostic manner.