#!/bin/bash
cat /sys/class/net/$1/statistics/rx_bytes | \
awk '{ mbytes = $1 / 1024 / 1024 ; printf "RX: %.2f MiB, ", mbytes }'
cat /sys/class/net/$1/statistics/tx_bytes | \
awk '{ mbytes = $1 / 1024 / 1024 ; printf "TX: %.2f MiB\n", mbytes }'