nslink.NetNS is possibly not safe to use in multithreaded applications

[philipp-karcher]

We have been dealing with very mysterious deadlocks in a multithreaded application, and I believe that nslink.NetNS is the culprit. It calls os.fork in its constructor, which is unsafe when mixed with threads (and for this reason deprecated in Python 3.12):

https://docs.python.org/3/library/os.html#os.fork
https://discuss.python.org/t/concerns-regarding-deprecation-of-fork-with-alive-threads/33555

[m4123]

Any update when this issue will be fixed?

[svinota]

It might be fixed now in the master branch after merging the async core, the whole NetNS functionality was rewritten.

The documentation update is on its way.

[svinota]

Please check if it works for you now, see the master branch (now released yet, so install/use from git).

Notice that you can use IPRoute(netns='...') instead of NetNS('...'); also AsyncIPRoute() is available, so you can use the library now in the asyncio-based projects.

The docs are being updated, will be merged/published asap.