Obtains a SecCode object for the code making the call.
The calling code is determined in a way that is subject to modification over
time, but obeys the following rules. If it is a UNIX process, its process id (pid)
- is always used. If it is an active code host that has a dedicated guest, such a guest
- is always preferred. If it is a host that has called SecHostSelectGuest, such selection
- is considered until revoked.
+ is always used.
@param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
@param self Upon successful return, contains a SecCodeRef representing the caller.