Creates a digest transform object.
- macOS 10.7+
The type of digest to compute. You may pass
NULLfor this parameter, in which case an appropriate algorithm will be chosen for you. Otherwise, use one of the values listed in Digest Constants.
The desired digest length. Note that certain algorithms may only support certain sizes. You may pass
0for this parameter, in which case an appropriate length will be chosen for you.
A pointer to a
CFError. This pointer will be set if an error occurred. This value may be
NULLif you do not want an error returned.
A new transform, or
nil on error.
This function creates a transform which computes a cryptographic digest.