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# startServicePrincipal()

Start your XPC service listening for connections from the host application.

```
class func startServicePrincipal()
```

## Discussion

The purpose of this method is so that plug-ins don’t have to link against `PlugInKit.framework`. You can simply link against `FxPlug.framework` and call `[FxPrincipal startServicePrincipal]` from the service principal’s `main()` function.

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