---
title: setUnitNumber
framework: kernel
role: pseudoSymbol
path: kernel/ionetworkinterface/1811014-setunitnumber
---

# setUnitNumber

Assigns an unique unit number to this interface.

## Declaration

```occ
virtual bool setUnitNumber(
 UInt16unit ); 
```

## Parameters

- `unit`: The unit number assigned to this interface object.

## Return Value

Return Value Returns true to indicate success if the interface has not yet attached to the network stack, otherwise returns false.

## Overview

Overview This method is called internally before the interface is attached to the network stack, to assign an unique unit number to the interface object. The kIOInterfaceUnit property is also updated using the provided value.

## See Also

### Miscellaneous

- [addNetworkData](kernel/ionetworkinterface/1810235-addnetworkdata.md)
- [attachToDataLinkLayer](kernel/ionetworkinterface/1810250-attachtodatalinklayer.md)
- [clearInputQueue](kernel/ionetworkinterface/1810266-clearinputqueue.md)
- [controllerDidChangePowerState](kernel/ionetworkinterface/1810277-controllerdidchangepowerstate.md)
- [controllerDidOpen](kernel/ionetworkinterface/1810292-controllerdidopen.md)
- [controllerWillChangePowerState](kernel/ionetworkinterface/1810306-controllerwillchangepowerstate.md)
- [controllerWillClose](kernel/ionetworkinterface/1810322-controllerwillclose.md)
- [debuggerRegistered](kernel/ionetworkinterface/1810336-debuggerregistered.md)
- [detachFromDataLinkLayer](kernel/ionetworkinterface/1810351-detachfromdatalinklayer.md)
- [feedPacketInputTap](kernel/ionetworkinterface/1810364-feedpacketinputtap.md)
- [feedPacketOutputTap](kernel/ionetworkinterface/1810380-feedpacketoutputtap.md)
- [flushInputQueue](kernel/ionetworkinterface/1810398-flushinputqueue.md)
- [free](kernel/ionetworkinterface/1810410-free.md)
- [getController](kernel/ionetworkinterface/1810426-getcontroller.md)
- [getExtraFlags](kernel/ionetworkinterface/1810443-getextraflags.md)
- [getFlags](kernel/ionetworkinterface/1810460-getflags.md)
- [getIfnet](kernel/ionetworkinterface/1810471-getifnet.md)
- [getInterfaceState](kernel/ionetworkinterface/1810480-getinterfacestate.md)
- [getInterfaceType](kernel/ionetworkinterface/1810498-getinterfacetype.md)
- [getMaxTransferUnit](kernel/ionetworkinterface/1810513-getmaxtransferunit.md)
- [getMediaAddressLength](kernel/ionetworkinterface/1810531-getmediaaddresslength.md)
- [getMediaHeaderLength](kernel/ionetworkinterface/1810551-getmediaheaderlength.md)
- [getNamePrefix](kernel/ionetworkinterface/1810563-getnameprefix.md)
- [getNetworkData(const char *)](kernel/ionetworkinterface/1810574-getnetworkdata.md)
- [getNetworkData(const OSSymbol *)](kernel/ionetworkinterface/1810596-getnetworkdata.md)
- [getUnitNumber](kernel/ionetworkinterface/1810607-getunitnumber.md)
- [handleClientClose](kernel/ionetworkinterface/1810628-handleclientclose.md)
- [handleClientOpen](kernel/ionetworkinterface/1810645-handleclientopen.md)
- [init](kernel/ionetworkinterface/1810663-init.md)
- [initIfnetParams](kernel/ionetworkinterface/1810678-initifnetparams.md)
- [inputEvent](kernel/ionetworkinterface/1810692-inputevent.md)
- [inputPacket](kernel/ionetworkinterface/1810712-inputpacket.md)
- [isPrimaryInterface](kernel/ionetworkinterface/1810743-isprimaryinterface.md)
- [isRegistered](kernel/ionetworkinterface/1810763-isregistered.md)
- [lock](kernel/ionetworkinterface/1810783-lock.md)
- [performCommand](kernel/ionetworkinterface/1810800-performcommand.md)
- [powerStateDidChangeTo](kernel/ionetworkinterface/1810818-powerstatedidchangeto.md)
- [powerStateWillChangeTo](kernel/ionetworkinterface/1810839-powerstatewillchangeto.md)
- [registerOutputHandler](kernel/ionetworkinterface/1810858-registeroutputhandler.md)
- [removeNetworkData(const char *)](kernel/ionetworkinterface/1810886-removenetworkdata.md)
- [removeNetworkData(const OSSymbol *)](kernel/ionetworkinterface/1810904-removenetworkdata.md)
- [setFlags](kernel/ionetworkinterface/1810924-setflags.md)
- [setInterfaceState](kernel/ionetworkinterface/1810944-setinterfacestate.md)
- [setInterfaceType](kernel/ionetworkinterface/1810958-setinterfacetype.md)
- [setMaxTransferUnit](kernel/ionetworkinterface/1810979-setmaxtransferunit.md)
- [setMediaAddressLength](kernel/ionetworkinterface/1810991-setmediaaddresslength.md)
- [setMediaHeaderLength](kernel/ionetworkinterface/1811003-setmediaheaderlength.md)
- [unlock](kernel/ionetworkinterface/1811026-unlock.md)