title: how to add a network device to a network namespace with libnetlink?
body: <p>I am trying to do some operations on network devices (specifically <code>lo</code> and <code>eth0</code>) with libnetlink inside a user/net namespace, however I get <code>RTNETLINK answers: No such device</code>. When running the exact same code outside of any namespaces as root, the operation succeeds. So I suppose I need to add the devices to the user/netns. How can you do that using libnetlink?</p>