Send ps report after system restart (set as cron job to run every few minutes)

up.sh

#!/bin/bash

a=`cat /proc/uptime | cut -f 1 -d "."`
b=`cat ~/previous_uptime | cut -f 1 -d "."`

cp /proc/uptime ~/previous_uptime -f
if [ "$a" -gt "$b" ]; then
  # Regular behavior - Incremental times
  echo >> ~/uptime_report.txt
  echo >> ~/uptime_report.txt
  date >> ~/uptime_report.txt
  uptime >> ~/uptime_report.txt
  ps aux >> ~/uptime_report.txt
  echo Report created!
else
  # System was restarted!

  echo | mail user@example.net -A ~/uptime_report.txt -s "`hostname` process report"
  rm ~/uptime_report.txt
  echo Message sent! 
fi