#!/bin/bash
# https://www.unixteacher.org/blog/linux/display-packets-per-second-on-linux/

time="1"     # one second
int="enp3s0f0"   # network interface

while true
do
	txpkts_old="`cat /sys/class/net/$int/statistics/tx_packets`" # sent packets
	rxpkts_old="`cat /sys/class/net/$int/statistics/tx_packets`" # recv packets
		sleep $time
	txpkts_new="`cat /sys/class/net/$int/statistics/tx_packets`" # sent packets
	rxpkts_new="`cat /sys/class/net/$int/statistics/tx_packets`" # recv packets
	txpkts="`expr $txpkts_new - $txpkts_old`"		     # evaluate expressions for sent packets
	rxpkts="`expr $rxpkts_new - $rxpkts_old`"		     # evaluate expressions for recv packets
		echo "tx $txpkts pkts/s - rx $rxpkts pkts/ on interface $int"
done