[Samba] How to identify the operating system of a client?

[Stephan Roth]

My goal is to distinguish between Mac and Windows clients on a Samba 
server in order to provide shares with vfs_fruit only to Mac clients.

So I assumed using the variable substitution %a which contains the 
architecture of the remote machine would be the correct way forward.
But as it turns out, a Windows 10 client is reported as having the 
architecture "OSX".

Short of agressively scanning a remote client with nmap, does anyone 
have a suggestion on how to solve this problem?

Thanks!

- Stephan

I'm using Samba 4.5.12-Debian