#!/bin/bash
if [ -n "$1" ]; then
  eth_name=$1
else
  eth_name="eth0"
fi
i=0
send_o=`ifconfig $eth_name | grep bytes | awk '{print $6}' | awk -F : '{print $2}'`
recv_o=`ifconfig $eth_name | grep bytes | awk '{print $2}' | awk -F : '{print $2}'`
send_n=$send_o
recv_n=$recv_o
while [ $i -le 100000 ]; do
  send_l=$send_n
  recv_l=$recv_n
  sleep 1
  send_n=`ifconfig $eth_name | grep bytes | awk '{print $6}' | awk -F : '{print $2}'`
  recv_n=`ifconfig $eth_name | grep bytes | awk '{print $2}' | awk -F : '{print $2}'`
  i=`expr $i + 1`
  send_r=`expr $send_n - $send_l`
  recv_r=`expr $recv_n - $recv_l`
  total_r=`expr $send_r + $recv_r`
  send_ra=`expr \( $send_n - $send_o \) / $i`
  recv_ra=`expr \( $recv_n - $recv_o \) / $i`
  total_ra=`expr $send_ra + $recv_ra`
  sendn=`ifconfig $eth_name | grep bytes | awk -F \( '{print $3}' | awk -F \) '{print $1}'`
  recvn=`ifconfig $eth_name | grep bytes | awk -F \( '{print $2}' | awk -F \) '{print $1}'`
  clear
  echo "==================================================" 
  echo  "Last second  :   Send rate: $send_r Bytes/sec  Recv rate: $recv_r Bytes/sec  Total rate: $total_r Bytes/sec"
  echo  "Average value:   Send rate: $send_ra Bytes/sec  Recv rate: $recv_ra Bytes/sec  Total rate: $total_ra Bytes/sec"
  echo  "Total traffic after startup:    Send traffic: $sendn  Recv traffic: $recvn"
  echo "=================================================="
done