#!/usr/bin/env bash
# Read /proc/stat CPU utilization
read -r cpu u n s i io ir st g gn < /proc/stat
total1=$((u + n + s + i + io + ir + st + g + gn))
idle1=$((i + io))
sleep 0.2
read -r cpu u n s i io ir st g gn < /proc/stat
total2=$((u + n + s + i + io + ir + st + g + gn))
idle2=$((i + io))

total_diff=$((total2 - total1))
idle_diff=$((idle2 - idle1))

if [ "$total_diff" -gt 0 ]; then
    cpu_usage=$(( (total_diff - idle_diff) * 100 / total_diff ))
else
    cpu_usage=0
fi

echo "$cpu_usage"