Monitor network speed

nettx

#!/bin/bash

if [[ $# -ne 1 ]]; then
  echo "Usage: $0 <interface>"
  ls /sys/class/net
  exit 1
fi

while true; do
  rx1=$(cat "/sys/class/net/$1/statistics/rx_bytes")
  tx1=$(cat "/sys/class/net/$1/statistics/tx_bytes")
  sleep 1
  rx2=$(cat "/sys/class/net/$1/statistics/rx_bytes")
  tx2=$(cat "/sys/class/net/$1/statistics/tx_bytes")
  printf "\r\e[KRX: %sB/s TX: %sB/s" "$(numfmt --to=iec $((rx2 - rx1)))" "$(numfmt --to=iec $((tx2 - tx1)))"
done