#!/bin/sh
# netinfo <delay> <interface>

last_rx=0
last_tx=0
while true; do
    ipaddr=` ifconfig $2 | awk '/inet addr/{ split($2,s,/:/); print s[2]; }' `
    if [ $ipaddr != "" ]; then

        link="(` cat /proc/net/wireless | grep $2 | awk '{print $3}' `)"
        prefix="$2[{kc}$ipaddr{-}$link]"
        stats=` cat /proc/net/dev | grep $2 | tr : \ `

        rx=` echo $stats | cut -d\  -f2 `
        tx=` echo $stats | cut -d\  -f10 `

        up=$(( ( $tx - $last_tx ) / $1 ))
        dn=$(( ( $rx - $last_rx ) / $1 ))

        echo -n "$prefix "
        #note: 8/1024 == 128 >> bytes to kilobits
        echo "$up $dn" | awk '{printf "{kg}%06.2f{kw}/{kr}%06.2f{kw}\n",$1/128,$2/128}'

        last_tx=$tx
        last_rx=$rx
        sleep $1
    else
        echo "$2 not connected"
        sleep 15
    fi
done