[RFC] LXC and network namespace issue

The problem with stoping/restarting the container.

Upon completion of the container, the parent process received signal SIGCHLD and exit code (by waitpid()).

During the 10-25ms after the completion of the container, we can not create vlan-interface (for restart).
The system returns an error codeEEXIST.

Another problem with the network interface type "phys".
Before running the container we save ifindex network physical interface (by if_nametoindex()).
We need to restore the name of network interface have the type phys (by saved ifindex) upon completion of the container,
  but the system returns an error ENODEV. 10-25 ms later the action is completed successfully!

Is there a way to wait for the release of all resources (from userspace)?