# Check spell http://www.shellcheck.net/# online, or download, to test!
-# Bash have variable when call an executable, $0 = CommandName, $1..$N = Arguments
-commandName=$(basename "$0")
-argumentsRequired="first second"
-###### Function declaration
-# My first function, display usage info
- echo "This script require arguments!"
- echo -e "\nUsage:\n$0 [${argumentsRequired}] \n"
-# My second function, check if
-f_check_correct_parameters()
+############################################################ Function declaration
+# This function, display usage info
+ echo -e "\n--------------------------------------------------"
+ echo "| This function teach you how this script works"
+ echo -e "| Usage:\n| $0" # -e option allow use \n
+ echo "| ${optionHelp} = Print usage"
+ echo "| ${optionSay} = Print echo with message"
+ echo "| ${optionPrintOptions} = Print all options"
+ echo "| ${optionAuthor} = Print author's name"
+ echo -e "--------------------------------------------------"
+ echo -e "\n--------------------------------------------------"
+ echo " I want to say: ${1}"
+ echo -e "--------------------------------------------------"
+ echo -e "\n--------------------------------------------------"
+ echo " The author is: vgoni"
+ echo -e "--------------------------------------------------"
-# if less than ${argumentsLimit} arguments supplied, display usage
- if [ $# -le ${argumentsLimit} ]
+ echo -e "\n--------------------------------------------------"
+ echo " Printing arguments..."
+ echo " The number of arguments provided is: ${Nargs}"
+ for ((i=0; i < ${Nargs}; i++))
+ echo " The argument $((i+1)): ${args[$i]}"
+ echo " No more arguments!"
+ echo -e "--------------------------------------------------"
+# Check if are provided correct arguments
+ echo " Evaluation options, number of arguments: ${Nargs}"
+ echo " Options: ${options}"
+############################################################ End Function declaration
+# First of all, store arguments in a variable.
+# Bash have variable when call an executable, $0 = CommandName, $1..$N = Arguments
+# We store arguments in an array. If a function is called, you cannot access to them if not are global variables
+# because they are overwrited by function arguments.
+Nargs=(${#}) # Number of arguments
+# We define options, using getopt
+# -o Each single character stands for an option
+# -l Long name for each option
+# : after an option (short or long) tells that option is required argument
+# :: tells is a optional argument
+# For extension take a look here: http://www.bahmanm.com/blogs/command-line-options-how-to-parse-in-bash-using-getopt
+options=$(getopt -o hs:ao -l help,say:,author,options -- "${@}")
+ echo " Error: Detected invalid option"
+# -o hs:ao = h & a option, no arguments; s option with a required option;
+# -l help,say:,author = same.
+# Declarate variables with options to clarify
+optionAuthor="-a|--author"
+optionPrintOptions="-o|--options"
+# We define some global variables
+commandName=$(basename "$0") # Extract name from first variable
+commandPath=$(pwd) # Get the path with command pwd
echo "------- My second script begins execution..."
echo "--------------------------------------------"
-echo " Executing command: ${commandName}"
+echo " Executing command: ${commandName}"
echo " At path: ${commandPath}"
-echo " You want to have ${argumentsLimit} and provide ${#}"
-f_check_correct_parameters
-# check whether user had supplied -h or --help . If yes display usage
- if [[ ( $# == "--help") || $# == "-h" ]]
+# Call a function to evaluate arguments as options
+# We are going to check the all the options shifting them.
+# Using shift, the positional parameters are shifted to the left by this number, N.
+# Using case syntaxis, more info: http://tldp.org/LDP/Bash-Beginners-Guide/html/sect_07_03.html
+ echo "Processing option: ${1}"
+ -h|--help) f_display_usage ;; # Call function
+ -s|--say) f_say $2 ; shift ;; # Call function with argument, and discard argument
+ -a|--author) f_author ;; # Call a function to print author
+ -o|--options) f_options ;; # Call a function to print options
+ *) echo "Unknown option: $1" ; f_display_usage ; break ;;
echo "------- My second script end now!"
echo "---------------------------------"
-###### End Function declaration
