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# detachNewThreadSelector(_:toTarget:with:)

Detaches a new thread and uses the specified selector as the thread entry point.

```
class func detachNewThreadSelector(_ selector: Selector, toTarget target: Any, with argument: Any?)
```

## Parameters

`selector`

The selector for the message to send to the target. This selector must take only one argument and must not have a return value.

`target`

The object that will receive the message `aSelector` on the new thread.

`argument`

The single argument passed to the target. May be `nil`.

## Discussion

The objects `aTarget` and `anArgument` are retained during the execution of the detached thread, then released. The detached thread is exited (using the [`exit()`](/documentation/Foundation/Thread/exit()) class method) as soon as `aTarget` has completed executing the `aSelector` method.

If this thread is the first thread detached in the application, this method posts the [`NSWillBecomeMultiThreaded`](/documentation/Foundation/NSNotification/Name-swift.struct/NSWillBecomeMultiThreaded) with object `nil` to the default notification center.

## See Also

[`isMultiThreaded()`](/documentation/Foundation/Thread/isMultiThreaded())

Returns whether the application is multithreaded.

[`current`](/documentation/Foundation/Thread/current)

Returns the thread object representing the current thread of execution.


---

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