bash

    while [ "x$INET_IPM" == "x" ]; do
       
      i=`ip a s wlan0 | grep "inet " | grep -v "169.254" | awk '{print $2}'`
      if [ "x$i" != "x" ]; then
        INET_IFACE="wlan0"
        INET_IPM="$i"
        break; fi
       
      i=`ip a s eth0 | grep "inet " | grep -v "169.254" | awk '{print $2}'`
      if [ "x$i" != "x" ]; then
        INET_IFACE="eth0"
        INET_IPM="$i"
        break; fi
       
      if [ "x$INET_IPM" == "x" ]; then                                                                                                           
        [ "x$wait" != "x" ] || echo -n "waiting for ip on $INET_IFACE .."
        echo -n "."
        wait=now
        sleep 3
      fi
    done
    echo
        
    INET_IP=${INET_IPM%/*}
    INET_GW=`ip r | grep default | awk '{print $3}'`