Specify the class of a keychain item.
Keychain items come in a variety of classes according to the kind of data they hold, such as passwords, cryptographic keys, and certificates. The item's class dictates which attributes apply and enables the system to decide whether or not the data should be encrypted on disk. For example, passwords obviously require encryption, but certificates don't because they are not secret.
Use the key and one of the corresponding values listed here to specify the class for a new item you create with a call to the
Sec function by placing the key/value pair in the