Macworld recently shared an article explaining the difference between Locked files and other file permissions. By locking a file, it’s possible to stop your system from overwriting files, if you have a few that need to remain unchanged.
Stop Overwriting Files with a Lock
If you choose Get Info on a particular file you can lock it.
- Select a file and press Command (⌘) + I, or go to File > Get Info from the menu bar.
- Check the box next to Locked.
This will prevent apps from overwriting the file. Additionally, if you accidentally delete the file, it will stay in Trash because macOS can’t empty the Trash if it has a locked file inside. Keep in mind thought that if you sync these files with iCloud Drive, the “locked” property doesn’t get transferred.