.... don't. Just. Don't.
Instead: reopen any open logfiles if you receive a SIGHUP, and let programs like logrotate take care of the rotation.
And never, ever, just don't, rotate the logfile on startup.
If you are running
tail -f on the log file while restarting the
service and get no feedback, you've been hit by this bad behaviour.
(Yes, you can use
-F but you shouldn't have to. Just sayin'.)