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+    #!/bin/bash -e
+    
+    #TODO
+    # 1. One trap is not fully functioning see TODO further down.
+    
+    #Options if no terminal argument is given
+    OPTIONS=\
+    "(h)elp
+    (p)rocesses
+    (u)sers
+    (d)ownload
+    (f)iles
+    (q)uit"
+    
+    
+    
+    ### Supported functionality ###
+    
+    function help {
+        echo -e "\\033[1m${0}\\033[0m usage:
+        \\e[0;31m-h\\e[0m             Prints this help
+        \\e[0;31m-p\\e[0m             Show total number of processes and list the 10 most not nice ones
+        \\e[0;31m-u \\e[0m            Show all local users and their login shell with less
+        \\e[0;31m-d\\e[0m             Asks for path and downloads Stallman's frontpage to given path
+                                       (defaults to /tmp/ if no path given)
+        \\e[0;31m-f\\e[0m             Asks for directory and returns total disk space used by it in MB (recursively)
+    
+        If the arguments '-q' or '-h' is given no additional commands will be executed,
+            otherwise multiple arguments can be given to this program and executed in order.
+        However, if no arguments are given at launch, the user is presented with choices inside of the program.
+            In this menu the user can choose between these options by entering the integer (1-6)
+        "
+    
+    }
+    
+    function processes {
+        #Number of processes (excludes the title row)
+        let PROCS=$(ps -eo pid,cmd,ni --sort=-ni | wc -l)-1
+        echo "Number of processes: $PROCS"; echo
+    
+        #show 10 lowest NIce processes
+        echo "Most NOT nice processes: "
+        ps -eo pid,cmd,ni --sort=-ni | tail -n 10
+        echo
+    }
+    
+    function users {
+        awk -F: '{ print "User: " $1 "\nShell: " $7 "\n"}' < /etc/passwd | less
+    }
+    
+    function download {
+        FILE_NAME="stallman.html"
+    
+        echo "In what directory do you wish to save this file? (either absolute or relative path)"
+        read MY_PATH
+    
+        while [ ! -d "$MY_PATH" ]
+        do
+            if [ -z "$MY_PATH" ]; then
+                echo "No path given, defaulting to /tmp/"
+                MY_PATH="/tmp/"
+                break
+            fi
+            echo -e "The folder '${MY_PATH}' does not exist!\n"
+            echo "In what directory do you wish to save this file? (either absolute or relative path)"
+            read MY_PATH
+        done
+    
+        wget https://stallman.org/ -O "${MY_PATH}/${FILE_NAME}"
+    }
+    
+    function files {
+        echo "Enter the directory (absolute or relative path) which you'd like to know the size of"
+        read MY_PATH
+        #MY_PATH=$(pwd)
+    
+        UNIT="MB"
+        let UNIT_RAW=1024*1024
+    
+        SIZE=$(df -B $UNIT_RAW "$MY_PATH" | awk 'FNR==2 {print $2}')
+    
+        # Unexpected output (awk parsing return empty string)
+        if [ -z "$SIZE" ]; then
+            return 1
+        fi
+    
+        echo "Disk space used by $MY_PATH is $SIZE $UNIT"
+    }
+    
+    
+    
+    ### Helper functions ###
+    
+    function ask_quit {
+        echo "Would you like to quit? (y/n)"
+        read PROMPT
+    
+        if [ "$PROMPT" = "y" ]; then
+            echo "OK exiting..."
+            exit 0
+        fi
+    
+        return
+    }
+    
+    #send all arguments here to see if they are valid (with "$@")
+    #if either help or any invalid options are given it will not continue with other commands
+    function arguments_valid {
+        while [ $# -gt 0 ]
+        do
+            case $1 in
+                "-h")
+                    help
+                    exit 0
+                    ;;
+                "-p")
+                    ;;
+                "-u")
+                    ;;
+                "-d")
+                    ;;
+                "-f")
+                    ;;
+                *)
+                    echo "Invalid detected. Bye!"
+                    exit 1
+                    ;;
+            esac
+            shift
+        done
+    }
+    
+    function menu {
+    
+        #present exit dialogue on SIGINT if already in menu
+        trap ask_quit SIGINT
+    
+        echo -e "\tNo arguments were given, choose between the options below by entering the integer (1-6)\n"
+    
+        select OPTION in ${OPTIONS};
+        do
+            #TODO! The below trap seems to disable the 'ask_quit' trap above,
+                 # so it seems to be a problem with changing the trap like this multiple times.
+                 # ideally it should change back and forth depending on if we're in menu or in these functions below.
+            #return to menu on SIGINT
+            #trap menu SIGINT
+            case $OPTION in
+                "(h)elp")
+                    help
+                    ;;
+                "(p)rocesses")
+                    processes
+                    ;;
+    
+                "(u)sers")
+                    users
+                    ;;
+    
+                "(d)ownload")
+                    download
+                    ;;
+    
+                "(f)iles")
+                    files
+                    ;;
+    
+                "(q)uit")
+                    echo "Bye!"
+                    break
+                    ;;
+                *)
+                    echo "Invalid option. Bye!"
+                    break
+                    ;;
+    
+            esac
+        done
+    }
+    
+    
+    
+    
+    ### Option menu for user ###
+    
+    #The program starts here!
+    echo -e "\e[1;35mWelcome to the exam script of 2018! Let's begin\e[0m\n"
+    
+    #Hint:
+    #Can test traps with
+    #ps aux | grep exam2018_test.sh
+    #kill -QUIT pid
+    #kill -INT  pid
+    
+    #Default behavior ask for confirmation to quit on these signals
+    trap ask_quit SIGQUIT SIGINT
+    
+    #No options presents user with alternatives in terminal
+    if [ $# -eq 0 ]; then
+        menu
+    
+    #Arguments given to program
+    else
+        arguments_valid "$@"
+    
+        while [ $# -gt 0 ]
+        do
+            case $1 in
+                "-h")
+                    help
+                    exit 0
+                    ;;
+                "-p")
+                    processes
+                    ;;
+                "-u")
+                    users
+                    ;;
+                "-d")
+                    download
+                    ;;
+                "-f")
+                    files
+                    ;;
+                *)
+                    echo "Invalid option. Bye!"
+                    exit 1
+                    ;;
+            esac
+            shift
+        done
+        exit 0
+    fi