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1

help()
{
    header
    echo
    echo 'Usage: cckiller [OPTIONS] [N]'
    echo 'N : number of tcp/udp    connections (default 100)'
    echo
    echo 'OPTIONS:'
    echo "-h | --help: Show    this help screen"
    echo "-k | --kill: Block the offending ip making more than N connections"
    echo '-s | --show: Show The TOP "N" Connections of System Current'
    echo "-b | --banip: Ban The IP or IP subnet like cckiller -b 192.168.1.1"
    echo "-u | --unban: Unban The IP or IP subnet which is in the BlackList of iptables"
    echo
}

if [ $# -lt 2 ]; then
    help
fi

2

# Notes:
#  - Please install "jq" package before using this driver.
usage() {
    err "Invalid usage. Usage: "
    err "\t$0 init"
    err "\t$0 mount <mount dir> <json params>"
    err "\t$0 unmount <mount dir>"
    exit 1
}

err() {
    echo -ne $* 1>&2
}

...

if [ $# -lt 2 ]; then
    usage
fi
....