【shell脚本】计算网卡速率

#! /bin/bash

eth="br-lan"

timer=1

# Setting IFS (input field separator) value as ","
IFS=' '

# Reading the split string into array

read -ra arr <<< "$(cat /proc/net/dev | grep $eth)"

in_old=${arr[1]}
out_old=${arr[9]}

while true

do

   sleep ${timer}
   
   read -ra arr <<< "$(cat /proc/net/dev | grep $eth)"

   in=${arr[1]}

   out=${arr[9]}

   dif_in=$(((in-in_old)/timer))

   #dif_in=$((dif_in/102400))

   dif_in=$(echo | awk "{print $dif_in/131072}" )

   dif_out=$(((out-out_old)/timer))

   #dif_out=$((dif_out/102400))

   dif_out=$(echo | awk "{print $dif_out/131072}" )

   printResult=$(echo ${dif_in}","${dif_out})

   echo $printResult > DashBoard.txt

   ct=$(date +"%F %H:%M:%S")

   echo "${ct} -- DownLink: ${dif_in} Mbit/s  UpLink: ${dif_out} Mbit/s"

   in_old=${in}

   out_old=${out}

done


exit 0