#!/bin/bash
p="$(lsof -i tcp:31416 -Fp -a -c java | sed -rn 's/^p//p')"
if [[ $p ]]; then
    kill $p
fi
cd /a/opt/gnirehtet
./gnirehtet rt &>/tmp/rt &
# note, to kill it, you need to also kill
# lsof -i tcp:31416
# and maybe unplug adb cable
# note, ping results in log message: dropping invalid packet

tail -F /tmp/rt ||: