So what I ended up doing is setting up a _end_of_line() method, which is called by either one of the two methods that handle the work of managing file names. This method peeks into the file, and sets an environment variable to the file's EOL ('\n' or '\r\n').

The methods deeper into the application have been modified to use that line ending in the environment variable when they open the respective file later on in the process.

Works pretty slick.