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# allocateRenderResources()

Allocates resources required to render audio.

```
func allocateRenderResources() throws
```

## Discussion

- <doc://com.apple.documentation/documentation/Swift/false> if the operation failed.

## Discussion

Hosts must call this before beginning to render. Subclasses should call the superclass implementation.

This version 3 method is bridged to the version 2 [`AudioUnitInitialize(_:)`](/documentation/AudioToolbox/AudioUnitInitialize(_:)) API.

> Handling Errors in Swift:
> In Swift, this method returns `Void` and is marked with the `throws` keyword to indicate that it throws an error in cases of failure.
> 
> You call this method in a `try` expression and handle any errors in the `catch` clauses of a `do` statement, as described in [Error Handling](https://docs.swift.org/swift-book/LanguageGuide/ErrorHandling.html) in [The Swift Programming Language](https://docs.swift.org/swift-book/) and `About Imported Cocoa Error Parameters`.

---

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