BSD 4.4 based operating systems, when running at security level 1, allow the root user to clear the immutable and append-only flags for files by unmounting the file system and using a file system editor such as fsdb to directly modify the file through a device.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Bsd | Bsd | 4.4 (including) | 4.4 (including) |