---
title: musicalTimeLocationProc
framework: audiotoolbox
role: symbol
role_heading: Instance Property
path: audiotoolbox/hostcallbackinfo/musicaltimelocationproc
---

# musicalTimeLocationProc

Your callback function that provides musical timeline information to an audio unit. May be NULL.

## Declaration

```swift
var musicalTimeLocationProc: HostCallback_GetMusicalTimeLocation?
```