Bash script for displaying the CPU and GPU temperatures of Raspberry Pi 3B+

pi_temperatures.sh

#!/usr/bin/env bash

# Display the CPU and GPU temperatures of Raspberry Pi 3B+ 

set -e

cpu_temp=$(</sys/class/thermal/thermal_zone0/temp)
cpu_temp=$(printf %.1f $((10 * cpu_temp/1000))e-1)

gpu_temp=$(vcgencmd measure_temp)
gpu_temp=${gpu_temp%"'C"}
gpu_temp=${gpu_temp#temp=}

celsius_sign=$'\xc2\xb0'C

echo "CPU temperature: $cpu_temp $celsius_sign"
echo "GPU temperature: $gpu_temp $celsius_sign"

On retropie, the default .bashrc file already defines a function retropie_welcome which provides key system metrics including the temperatures.