Sending out notifications when either the daemon or the target process stop running.

watchdog.sh

#!/usr/bin/env bash

if [[ $# < 2 ]]; then
	echo "Usage: watchdog <pcs> <email>"
	exit 1
fi

svr="$(hostname)"
pcs=$1
pcsdetail=$(ps --no-heading -p $pcs)
email=$2

trap "printf \"Daemon died on $svr!\\n \" | mail -s \"Daemon died on $svr!\" $email" 0
read -d '' script <<"EOF"
import sys;
import os;
import time;

while os.path.exists('/proc/pid'):
    time.sleep(10);
EOF
python <<< "${script/pid/$pcs}"