---
title: I/O Audio Unit Function Selectors
framework: audiotoolbox
role: collectionGroup
role_heading: API Collection
path: audiotoolbox/1585807-i_o_audio_unit_function_selector
---

# I/O Audio Unit Function Selectors

Audio unit component selectors, specific to I/O audio units, that correspond to functions in the audio unit API.

## Topics

### Constants

- [kAudioOutputUnitRange](audiotoolbox/kaudiooutputunitrange.md)
- [kAudioOutputUnitStartSelect](audiotoolbox/kaudiooutputunitstartselect.md)
- [kAudioOutputUnitStopSelect](audiotoolbox/kaudiooutputunitstopselect.md)

## See Also

### Input/Output

- [I/O Audio Unit Properties](audiotoolbox/1534116-i_o_audio_unit_properties.md)
- [Inter-App Output Unit Property IDs](audiotoolbox/1621039-inter-app-output-unit-property-ids.md)
- [Inter-App Audio Unit Property IDs](audiotoolbox/1621038-inter-app-audio-unit-property-ids.md)
- [Output Unit Parameters](audiotoolbox/1389916-output_unit_parameters.md)
- [AUNetReceive Properties](audiotoolbox/1534109-aunetreceive-properties.md)
- [AUNetSend Properties](audiotoolbox/1534207-aunetsend-properties.md)
- [AUNetSend Parameters](audiotoolbox/1389633-aunetsend-parameters.md)
- [AUNetReceive Parameters](audiotoolbox/1389920-aunetreceive-parameters.md)
- [AUNetSendPresetFormat Properties](audiotoolbox/1534212-aunetsendpresetformat-properties.md)
- [Net Status Audio Unit Parameters](audiotoolbox/1389891-net-status-audio-unit-parameters.md)
- [AudioOutputUnitMIDICallbacks](audiotoolbox/audiooutputunitmidicallbacks.md)
- [AudioOutputUnitStartAtTimeParams](audiotoolbox/audiooutputunitstartattimeparams.md)