To do this absolutely properly, you neet to write a virtual filesystem. And I imagine that's quite difficult to do in perl.

By "absolutely properly", I mean handling all possible operations on the file.

The next best thing may be to move the samba share to a Linux server, and use the pipes, but my gut tells me there's race conditions, timeouts, etc., which would mean that in some scenarios, bossman may overwrite files.

Actually, I take some of that back - what you really want is to pull it off the share, and make it accessable only to multi-user-editing software. Period. And tell bossman that due to the problems you've had with the file, you've found a solution that will keep all changes safe.

To be honest, it's probably easier to quit and find a new job ;->. But that's no guarantee you'll get a brighter PHB...