checkip.awk

BEGIN {
    FS="."
    ex = "false"
    split(address, ip, ".")
}
{
    split($0, range, "[-.]")
    for (i=1; i<5; i++) {
        if (ip[i] < range[i] || ip[i] > range[i+4])
            break;
        else if ((ip[i] > range[i] && ip[i] < range[i+4]) || i == 4)
            ex = "true"
    }
}
END {
    print ex
}