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# probeResource(resource:replyHandler:)

Requests that the file system probe the specified resource.

```
func probeResource(resource: FSResource, replyHandler reply: @escaping @Sendable (FSProbeResult?, (any Error)?) -> Void)
```

## Parameters

`resource`

The [`FSResource`](/documentation/FSKit/FSResource) to probe.

`reply`

A block or closure that your implementation invokes when it finishes the probe or encounters an error. Pass an instance of [`FSProbeResult`](/documentation/FSKit/FSProbeResult) with probe results as the first parameter if your probe operation succeeds. If probing fails, pass an error as the second parameter.

## Discussion

Implement this method to indicate whether the resource is recognizable and usable.

---

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