enzotib

#!/bin/bashexport LC_ALL=Ciface="$1"if [[ -z "$iface" ]]; then  echo "Interface not specified: using eth0"  iface="eth0"fiif ! /sbin/ifconfig >/dev/null 2>/dev/null "$iface"; then  echo "Invalid interface"  exit 1firxbytes() {  iface="$1"  /sbin/ifconfig "$iface" | awk '/RX bytes/ { split($2, a, ":"); print a[2] }'}txbytes() {  iface="$1"  /sbin/ifconfig "$iface" | awk '/TX bytes/ { split($6, a, ":"); print a[2] }'}tot_rxbytes_old="$(rxbytes "$iface")"tot_txbytes_old="$(txbytes "$iface")"sleep 1while true; do  tot_rxbytes="$(rxbytes "$iface")"  tot_txbytes="$(txbytes "$iface")"  rxrate="$(echo "scale=2; ($tot_rxbytes - $tot_rxbytes_old)/1024" | bc)"  txrate="$(echo "scale=2; ($tot_txbytes - $tot_txbytes_old)/1024" | bc)"  echo "rx rate: $rxrate KB/s, tx rate: $txrate KB/s"  tot_rxbytes_old=$tot_rxbytes  tot_txbytes_old=$tot_txbytes  sleep 1done