public static extern unsafe int SecKeychainItemCopyAttributesAndData( IntPtr itemRef, IntPtr info, IntPtr itemClass, SecKeychainAttributeList **attrList, uint *dataLength, void **data);
static extern unsafe OSStatus SecKeychainItemCopyAttributesAndData(IntPtr itemRef, SecKeychainAttributeInfo *info, ref SecItemClass itemClass, SecKeychainAttributeList **attrList, ref uint length, ref IntPtr outData);
static extern unsafe SecStatusCode SecKeychainItemCopyAttributesAndData(IntPtr itemRef, SecKeychainAttributeInfo *info, ref SecItemClass itemClass, SecKeychainAttributeList **attrList, IntPtr lengthRef, IntPtr outDataRef);