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# AudioHardwareIOProcStreamUsage

This structure describes which streams a given AudioDeviceIOProc will use. It is used in conjunction with kAudioDevicePropertyIOProcStreamUsage.

```
struct AudioHardwareIOProcStreamUsage
```

## Overview

- `mIOProc`: The IOProc whose stream usage is being specified.
- `mNumberStreams`: The number of streams being specified.
- `mStreamIsOn`: An array of UInt32’s whose length is specified by mNumberStreams. Each element of the array corresponds to a stream. A value of 0 means the stream is not to be enabled. Any other value means the stream is to be used.

---

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