API Notes for the SystemConfiguration framework
===============================================

callbacks
---------

There are several APIs that have a callback function and context structure in the
(Objective-)C API. In all cases an arbitrary object can be passed as the context, 
PyObjC will wrap that in the proper context structure for you.

SCDynamicStore
--------------

The ``context`` argument for ``SCDynamicStoreCreate`` is an arbitrary python object,
not a ``SCDynamicStoreContext`` structure as it is in C. The bridge will manage that
context structure for you.

SCNetworkCheckReachabilityByAddress
-----------------------------------

The ``address`` argument should have a value that can also be used with the Python socket
APIs (that is, a ``(host, port)`` tuple for IPv4 adresses or 
``(host, port, flowinfo, scopeid)`` tuple for IPv6 addresses). 

The ``addrlen`` argument should be ``objc._size_sockaddr_ip4`` for IPv4 addresses and
``_size_sockaddr_ip4`` for IPv6 adresses.