#!/bin/sh
#
# case_sh - mind (mind@metalshell.com)
#
# Basic example on the case structure
#
#       [ http://www.metalshell.com ]

# case word in [ pattern [ pattern ] ... ) list ;; ] esac
#
#    word: would be a sequence of words or integers we are going to parse
#      in: open's your case structure
# pattern: match this with the word we are parsing
#    list: commands to perform if a pattern is found (;;) closes the pattern
#    esac: closes our case structure
#
# case is a really good way to parse arguments passed to your program, something like
# what the example below shows.

print_usage()
{
        echo "Usage: $0 "
        echo "  -h      print this screen"
        echo "  -l      print a list"
        exit
}

print_list()
{
        echo "This is our list"
        echo " 1. first part"
        echo " 2. second part"
        echo " etc.."
        exit
}

# start our first case structure

# Create a for structure to run through all the arguments passed to our script
# note: "$@" is equivalent to "$1" "$2", etc.. $1 would be our first argument and so on..
for arg in "$@"
do
        # parse $arg
        case $arg
        in
                # match each option with $arg if a match is found proccess the list
                -h)     print_usage;;
                -l)     print_list;;
                # if an invalid option is given, print error and exit
                 *)
                        echo "Sorry but '$arg' is not a proper argument, please try -h";
                        exit;;
        esac
done