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# firmlink

File is a firmlink.

```
static var firmlink: FileFlags { get }
```

## Discussion

Firmlinks are used by macOS to create transparent links between
the read-only system volume and writable data volume. For example,
the `/Applications` folder on the system volume is a firmlink to
the `/Applications` folder on the data volume, allowing the user
to see both system- and user-installed applications in a single folder.

The corresponding C constant is `SF_FIRMLINK`.

> Note: This flag may only be changed by the superuser.

---

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