One of the more recent features in OSX is the ability to store the Desktop and Documents folders in iCloud. This is an incredibly convenient way to have the same files appear one all of your devices. If you are like me, however, the Desktop folder is often used as a dump for transient files. These are files that I am using for a particular project but will not remain there or possible anywhere else long term. I am often using them on only one particular machine and have no desire for the files to end up on my mobile devices. It turns out that Apple provides a way to keep files from syncing to iCloud and it is relatively easy to use.
Here is a snippet from the iCloud Fundamentals Documentation:
“One way to prevent files and directories from being stored in iCloud is to add the .nosync extension to the file or directory name. When iCloud encounters files and directories with that extension in the local container directory, it does not transfer them to the server. You might use this extension on temporary files that you want to store inside a file package, but that you do not want transferred with the rest of that package’s contents. Although items with the .nosync extension are not transferred to the server, they are still bound to their parent directory. When you delete the parent directory in iCloud, or when you evict the parent directory and its contents locally, the entire contents of that directory are deleted, including any .nosync items.”
Simply use a .nosync extension on a file or folder and it will not sync with iCloud. Now that is pretty simple.