---
title: start
framework: kernel
role: pseudoSymbol
path: kernel/ioaudiocontrol/1812313-start
---

# start

Starts a newly created IOAudioControl.

## Declaration

```occ
virtual bool start(
 IOService *provider); 
```

## Parameters

- `provider`: The IOAudioPort or IOAudioEngine that owns this control.

## Return Value

Return Value Returns true on success.

## Overview

Overview This is called automatically by IOAudioPort when addAudioControl() is called or by IOAudioEngine when addDefaultAudioControl() is called. It will only be called by the first call to either addAudioControl() or addDefaultAudioControl().

## See Also

### Miscellaneous

- [addUserClient](kernel/ioaudiocontrol/1812069-adduserclient.md)
- [addUserClientAction](kernel/ioaudiocontrol/1812079-adduserclientaction.md)
- [clientClosed](kernel/ioaudiocontrol/1812087-clientclosed.md)
- [createUserClient(task_t, void *, UInt32, IOAudioControlUserClient **)](kernel/ioaudiocontrol/1812095-createuserclient.md)
- [createUserClient(task_t, void *, UInt32, IOAudioControlUserClient **, OSDictionary *)](kernel/ioaudiocontrol/1812104-createuserclient.md)
- [detachUserClientsAction](kernel/ioaudiocontrol/1812113-detachuserclientsaction.md)
- [flushValue](kernel/ioaudiocontrol/1812123-flushvalue.md)
- [free](kernel/ioaudiocontrol/1812130-free.md)
- [getChannelID](kernel/ioaudiocontrol/1812135-getchannelid.md)
- [getCommandGate](kernel/ioaudiocontrol/1812146-getcommandgate.md)
- [getControlID](kernel/ioaudiocontrol/1812156-getcontrolid.md)
- [getIsStarted](kernel/ioaudiocontrol/1812169-getisstarted.md)
- [getValue](kernel/ioaudiocontrol/1812181-getvalue.md)
- [getWorkLoop](kernel/ioaudiocontrol/1812197-getworkloop.md)
- [hardwareValueChanged](kernel/ioaudiocontrol/1812208-hardwarevaluechanged.md)
- [init](kernel/ioaudiocontrol/1812219-init.md)
- [newUserClient](kernel/ioaudiocontrol/1812229-newuserclient.md)
- [performValueChange](kernel/ioaudiocontrol/1812237-performvaluechange.md)
- [removeUserClient](kernel/ioaudiocontrol/1812247-removeuserclient.md)
- [removeUserClientAction](kernel/ioaudiocontrol/1812259-removeuserclientaction.md)
- [sendValueChangeNotification](kernel/ioaudiocontrol/1812267-sendvaluechangenotification.md)
- [setChannelID](kernel/ioaudiocontrol/1812275-setchannelid.md)
- [setChannelName](kernel/ioaudiocontrol/1812281-setchannelname.md)
- [setControlID](kernel/ioaudiocontrol/1812283-setcontrolid.md)
- [setProperties](kernel/ioaudiocontrol/1812287-setproperties.md)
- [setReadOnlyFlag](kernel/ioaudiocontrol/1812291-setreadonlyflag.md)
- [setSubType(UInt32)](kernel/ioaudiocontrol/1812293-setsubtype.md)
- [setType(UInt32)](kernel/ioaudiocontrol/1812300-settype.md)
- [setUsage](kernel/ioaudiocontrol/1812305-setusage.md)
- [setValue](kernel/ioaudiocontrol/1812307-setvalue.md)
- [setValueAction](kernel/ioaudiocontrol/1812310-setvalueaction.md)
- [stop](kernel/ioaudiocontrol/1812316-stop.md)
- [updateValue](kernel/ioaudiocontrol/1812319-updatevalue.md)
- [validateValue](kernel/ioaudiocontrol/1812322-validatevalue.md)
- [withAttributes](kernel/ioaudiocontrol/1812328-withattributes.md)