sub get_measures {
    my $device = qr/\A\Q$_[0]\E\s/;  # pass device name as first argument

    local $/ = '';  # paragraph mode
    my ( $recv, $sent ) = map {
        /$device/ && /RX bytes\:(\d+) .*?TX bytes\:(\d+)/
            ? int( $1 / 1024 ), int( $2 / 1024 )
            : ()
        } qx[/sbin/ifconfig];

    return $recv, $sent;
    }