Run any Python script with Shadow using the Python plug-in. The limiations of Shadow itself apply in it as well:

• Everything must be non-blocking I/O and non-blocking system calls
• Using epoll for all otherwise-blocking I/O calls
• No multiprocessing / forking but threading is allowed

Please see the example.xml, which may be run in Shadow. For all executions in the context of the shadow plug-in (either the library to run it with Shadow or the standalone interpreter mentioned below), it requires its own preloaded library. You can either run ´export LD_PRELOAD="$HOME/.shadow/lib/libshadow-python-interpose.so"or execute Shadow with the--preload` argument (the latter one only works for Shadow itself, not for the standlone binaries).

shadow example.xml

You can also run all parts of the simulation outside of Shadow using the shadow-python binary. Included with the plug-in is a reimplementation of the Shadow echo plug-in in Python. This script can be run either from Python directly using your standard interpreter or using the plug-in shadow-python mentioned above (which mostly behaves like a regular Python interpreter). Run the server like this:

shadow-python tests/echo.py server 0.0.0.0

The execute the client:

shadow-python tests/echo.py client localhost

Substitute shadow-python with just python to run it with a regular interpreter. There is nothing special about the script other than them being written specifically to work with Shadow (meeting the requirements listed above such as using epoll).

The plug-in currently does not support Python 3 due to conflicts of running both in parallel. Interpreters and plug-ins for both exist and can be compiled. It might be possible to just load the Python 3 plug-in and it could just work if Python 2 is not enabled at all. However this has not been tested.

The plugin is called libshadow-plugin-python3.so and the interpreter is shadow-python3.

This plug-in was last tested and known to work with Shadow v1.11.1-23-g490e4f1