---
title: "SecTransformSetAttribute(_:_:_:_:)"
framework: security
role: symbol
role_heading: Function
path: "security/sectransformsetattribute(_:_:_:_:)"
---

# SecTransformSetAttribute(_:_:_:_:)

Sets a static value for an attribute in a transform.

## Declaration

```swift
func SecTransformSetAttribute(_ transformRef: SecTransform, _ key: CFString, _ value: CFTypeRef, _ error: UnsafeMutablePointer<Unmanaged<CFError>?>?) -> Bool
```

## Parameters

- `transformRef`: The transform whose attribute is to be set.
- `key`: The name of the attribute to be set. See doc://com.apple.security/documentation/Security/transform-attributes for a list of valid keys and possible values.
- `value`: The static value to set for the named attribute.
- `error`: A pointer that the function uses to provide an error object with details if an error occurs. The caller becomes responsible for the object’s memory. Pass NULL to ignore the error.

## Return Value

Return Value A Boolean set to true if the call succeeds. Otherwise, the error parameter contains information about the failure.

## Discussion

Discussion This function is useful for things like iteration counts and other non-changing values. It returns an error and the named attribute is not changed if SecTransformExecute(_:_:) has already been called on the transform. Compare this function with the SecTransformConnectTransforms(_:_:_:_:_:_:) function which sets derived data.