in reply to OS X troubleshooting help needed - parse filename & open file
I've been hacking Perl on OS X since the Public Beta and there are no differences between it and other *nixes for file handling (except the default filesystem is case-insensitive).
File and path handling has a lot of caveats. You should be using File::Spec, as suggested by roboticus, or Path::Class::(File|Dir). Where OS differences do exist those packages will handle it transparently.
In Section
Seekers of Perl Wisdom