GNURadio References:

In this subfolder, we have Flow Graph examples we used and made for this Project, along with any other useful resources noted in this README file.

Image Source. (Donate to GNU radio here)

When running a GNURadio Flow Graph which requires realtime scheduling, if the following error message in the console is encountered:

def main(top_block_cls=transceiver_CSS_loopback, options=None):   
    if gr.enable_realtime_scheduling() != gr.RT_OK:   
        gr.logger("realtime").warning("Error: failed to enable real-time scheduling.")
AttributeError: 'gnuradio.gr.gr_python.logger' object has no attribute 'warning'

The fix is to allow user's tasks gain the ability to ask for real-time scheduling. Run the following in a terminal:

echo "$(whoami)  -  rtprio  99" | sudo tee /etc/security/limits.d/99-rtprio.conf

Then perform a reboot and the problem should be solved. Thanks to This GitHub Issue #6923 for the solution.