Simple Stop Watch Timer Display for BASH

#!/bin/bash
######################################################################
#Copyright (C) 2022  Kris Occhipinti
#https://filmsbykris.com

#This program is free software: you can redistribute it and/or modify
#it under the terms of the GNU General Public License as published by
#the Free Software Foundation, either version 3 of the License, or
#(at your option) any later version.

#This program is distributed in the hope that it will be useful,
#but WITHOUT ANY WARRANTY; without even the implied warranty of
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#GNU General Public License for more details.

#You should have received a copy of the GNU General Public License
#along with this program.  If not, see <http://www.gnu.org/licenses/>.
######################################################################

[[ -f "/tmp/timer.stmp" ]] &&
  start="$(cat "/tmp/timer.stmp")" ||
  start="$(date +%s)"

echo $start > "/tmp/timer.stmp"
while [ 1 ]
do
  clear
  figlet -f bigmono12 $(($(date +%s) - start))
  sleep 1
done