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  "title" : "SetIdlePolicy"
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# SetIdlePolicy

Sets the pipe’s desired idle timeout.

```
virtual kern_return_t SetIdlePolicy(uint32_t idleTimeoutMs);
```

## Parameters

`idleTimeoutMs`

The amount of time, in milliseconds, before an active transfer is considered idle. If 0, the pipe isn’t considered idle if there’s an I/O request enqueued.

## Return Value

<doc://com.apple.documentation/documentation/DriverKit/kIOReturnSuccess> on success, or another value if an error occurs. See <doc://com.apple.documentation/documentation/DriverKit/error-codes>.

## Discussion

When a bulk or interrupt pipe is actively servicing an I/O request, it’s considered “busy” for the idle timeout value. For a more complete discussion of idle policies, refer to “Pausing IO” in `IOUSBHostFamily.h`.

---

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