---
title: refcon
framework: coremedia
role: symbol
role_heading: Instance Property
path: coremedia/cmbuffercallbacks/refcon
---

# refcon

Contextual data to be passed to all callbacks.

## Declaration

```swift
var refcon: UnsafeMutableRawPointer?
```

## Discussion

Discussion This can be NULL, if the callbacks don’t require it.

## See Also

### Properties

- [compare](coremedia/cmbuffercallbacks/compare.md)
- [CMBufferCompareCallback](coremedia/cmbuffercomparecallback.md)
- [CMBufferGetBooleanCallback](coremedia/cmbuffergetbooleancallback.md)
- [CMBufferGetTimeCallback](coremedia/cmbuffergettimecallback.md)
- [dataBecameReadyNotification](coremedia/cmbuffercallbacks/databecamereadynotification.md)
- [getDecodeTimeStamp](coremedia/cmbuffercallbacks/getdecodetimestamp.md)
- [getDuration](coremedia/cmbuffercallbacks/getduration.md)
- [getPresentationTimeStamp](coremedia/cmbuffercallbacks/getpresentationtimestamp.md)
- [getSize](coremedia/cmbuffercallbacks/getsize.md)
- [isDataReady](coremedia/cmbuffercallbacks/isdataready.md)
- [version](coremedia/cmbuffercallbacks/version.md)