---
title: init
framework: kernel
role: pseudoSymbol
path: kernel/ioaudiolevelcontrol/1811868-init
---

# init

Initializes a newly allocated IOAudioLevelControl with the given attributes

## Declaration

```occ
virtual bool init(
 SInt32 initialValue, 
 SInt32 minValue, 
 SInt32 maxValue, 
 IOFixed minDB, 
 IOFixed maxDB, 
 UInt32 channelID, 
 const char *channelName = 0, 
 UInt32 cntrlID = 0, 
 UInt32 subType = 0, 
 UInt32 usage = 0, 
 OSDictionary *properties = 0); 
```

## Parameters

- `initialValue`: The initial value of the control
- `minValue`: The lowest possible value the control may have
- `maxValue`: The highest possible value the control may have
- `minDB`: A fixed point representation of the db value matching minValue
- `maxDB`: A fixed point representation of the db value matching maxValue
- `channelID`: The ID of the channel(s) that the control acts on. Common IDs are located in IOAudioTypes.h.
- `channelName`: An optional name for the channel. Common names are located in IOAudioTypes.h.
- `cntrlID`: An optional ID for the control that can be used to uniquely identify controls.
- `properties`: Standard property list passed to the init() function of any new IOService. This dictionary gets stored in the registry entry for this service.

## Return Value

Return Value Returns true on success

## See Also

### Miscellaneous

- [create](kernel/ioaudiolevelcontrol/1811861-create.md)
- [setLinearScale](kernel/ioaudiolevelcontrol/1811880-setlinearscale.md)
- [setMaxDB](kernel/ioaudiolevelcontrol/1811889-setmaxdb.md)
- [setMaxValue](kernel/ioaudiolevelcontrol/1811896-setmaxvalue.md)
- [setMinDB](kernel/ioaudiolevelcontrol/1811907-setmindb.md)
- [setMinValue](kernel/ioaudiolevelcontrol/1811910-setminvalue.md)