It even sounds like it might be an easy way to clone your server to another PC as a method of backing it up. I haven't done any research yet on the best ways to back your server up. All of the forums, blogs, etc have lil backup addons, but if you're running a couple of sites with these components, then that'd get tedious to maintain.
As far as doing a sync on your entire xampp folder, you're probably going to run into a problem there.
The only two things you should need to sync is your htdocs folder (or whatever you've named it) and your MySQL database. I don't know where that's stored at on the server though, I haven't gone digging for it yet.
What I would do is install XAMPP on MAC using the proper installation version, then do the same on Windows. Next, try replacing the Mac's MySQL database with the one from the Windows server. That would probably be the main issue of compatibility being my guess. Then replace your htdocs folder with the one from the Windows server. This shouldn't be a problem at all.
Maybe someone who knows more about how the MySQL database works can tell you whether or not it can be replaced and still function or not. I just don't know enough about how it works to tell ya on that.
I will try to do some experimenting with it between Windows and Linux once I ever figure out how to get Linux configured correctly and get a better grasp on all that permissions bs. Haha.
Keep us informed on what you discover.
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