I Googled the heck out of this, but couldn’t find a recent/definitive answer.
How do I clear log files? Specifically my events.log file.
Simple: you don’t.
log4j2.xml in $OPENHAB_USERDATA defines how large a logfile can become before it’s rotated, and how many are kept.
This has all the hallmarks of an X Y problem. Why do you feel that you need to clear your log file? If you explain that, maybe the underlying issue can be fixed instead.