---
title: asyncRefCon
framework: coreservices
role: symbol
role_heading: Instance Property
path: coreservices/lslaunchurlspec/1448168-asyncrefcon
---

# asyncRefCon

A pointer to an arbitrary application-defined value, passed in the Carbon event notifying you of an application’s launch or termination (if you have registered for such notification). The value of this field can be NULL.

## Declaration

```swift
var asyncRefCon: UnsafeMutableRawPointer?
```

## See Also

### Configuring a Launch URL

- [appURL](coreservices/lslaunchurlspec/1443566-appurl.md)
- [itemURLs](coreservices/lslaunchurlspec/1443759-itemurls.md)
- [launchFlags](coreservices/lslaunchurlspec/1443957-launchflags.md)
- [passThruParams](coreservices/lslaunchurlspec/1445136-passthruparams.md)