#!/bin/bash



function show_help() {

    cat << ENDHELP

-a you can do stuff like that.

-b you can do stuff like that.

-c this is extremely fancy stuff.

ENDHELP

}



case $1 in

    --help)

        show_help

    ;;

    -a)

        sudo /path/to/other/script

    ;;

    -b)

        do_some_stuff

        do_another_stuff

    ;;

    -c)

        do_extremely_fancy_stuff

        do_another_extremely_fancy_stuff

        run_as_many_commands_as_you_want

    ;;

    *)

        echo "Run $0 --help"

    ;;

esac

• $0 is the script name.


• $1 is the first command line argument, $2 is the second, and so on.

Read bash manpage for reference.