SecTransformSetAttribute(_:_:_:_:)

Declaration

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 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

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

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.