Kill other roscore/master processes
I keep getting this error message when trying to run roscore:
roscore cannot run as another roscore/master is already running. Please kill other roscore/master processes before relaunching.
However, I only have one terminal window open. How could there already be a roscore running? I've tried quitting Terminal and restarting it and I've tried restarting my computer. It doesn't matter what I do - my computer thinks there is a roscore running even though there are no terminal windows open with roscore running in them. Is there a way to kill this invisible roscore so that I can run one in a window?