---
title: kSecTransformActionStartingExecution
framework: security
role: symbol
role_heading: Global Variable
path: security/ksectransformactionstartingexecution
---

# kSecTransformActionStartingExecution

An action that triggers just before starting execution of a custom transform.

## Declaration

```swift
let kSecTransformActionStartingExecution: CFString
```

## Discussion

Discussion Overrides the standard behavior that occurs just before starting execution of a custom transform. This is typically overridden to allow for initialization. This is used with the SecTransformOverrideTransformAction block.