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# AudioCodecMagicCookieInfo

A structure holding magic cookie information needed by some codecs.

```
struct AudioCodecMagicCookieInfo
```

## Overview

This structure is passed as input to the [`AudioCodecGetProperty(_:_:_:_:)`](/documentation/AudioToolbox/AudioCodecGetProperty(_:_:_:_:)) function for the `kAudioCodecPropertyFormatList` property. The first `4 + sizeof(void *)` bytes of the buffer pointed to by the function’s `outPropertyData` parameter contains this structure on input.

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