Shell Programming and Scripting

 
function mainmenu {
echo "--------------- MAIN MENU -------------------"
echo " 1. CH1 "
echo " 2. CH2 "
echo " 3. CH3 "
echo "Choose 1-3"
read choice
case $choice in
1)
    while :
    do
    submenu # calling another menu here
    case $subchoice in
        1)
               do something
               ;;
        2) 
              do something
              ;;
        3)
              do something
              ;;
        4)
              do something
             ;;
        5)
             mainmenu
             ;;
        6)
             uexit                    #  calling the function to exit
             exit 1 
             ;;
        esac
       done
       ;;
2)
     while :
     do
               submenu2 # calling another menu here
            case $subchoice2 in
            1)
                   do something
                   ;;
           2)
                  do something
                  ;;
           3)
                 while :
                 do
                                submenu3 # calling another menu here
                         case $subchoice3 in
                         1)
                                  do something
                                  ;;
                        2)
                                 do something
                                 ;;
                       3)
                                do something
                                ;;
                      4)
                               do something
                               ;;
                      5)
                                      submenu2
                              ;;
                     6)
                              uexit
                              exit 1 
                             ;;
                     esac
                    done
                    ;;
          4)
                    do something
                     ;;
          5) 
                    mainmenu
                     ;;
          6)
                     uexit
                    exit 1  
                     ;;
          esac
        done 
       ;;
3)
      do something
       ;;
4)
      uexit
      exit 1
    ;;
esac
return
}
mainmenu

#!/bin/bash


function main_menu()
{
    while :
    do
        echo
        echo "MAIN MENU"
        echo
        echo "1. Main Menu Option 1"
        echo "2. Main Menu Option 2"
        echo "3. Main Menu Option 3 To Sub-Menu"
        echo "4. Main Menu Option 4 To Quit"
        echo
        read -p "Choice: " m_choice
        echo
        
        case "$m_choice" in 
            1)  echo "Main Menu Option 1"
                echo
                ;;
            2)  echo "Main Menu Option 2"
                echo
                ;;
            3)  sub_menu
                ;;
            4)  exit 0
                ;;
            *)  echo "Bad Option"
                echo
                ;;
        esac
    done
}

function sub_menu()
{
    while :
    do
        echo
        echo "SUB MENU"
        echo
        echo "1. Sub-Menu Option 1"
        echo "2. Sub-Menu Option 2"
        echo "3. Sub-Menu Option 3 Back To Main Menu"
        read -p "Choice: " s_choice
        echo

        case "$s_choice" in
            1)  echo "Sub-Menu Option 1"
                echo
                ;;
            2)  echo "Sub-Menu Option 2"
                echo
                ;;
            3)  main_menu
                ;;
            *)  echo "Bad Option"
                echo
                ;;
        esac
    done
}

main_menu

exit 0

#!/bin/bash

IFS="|" # Split menus on |, so we can have spaces in titles

# Use parameters as a stack.  $1 is the current menu.
# we can add with set -- again, or remove with 'shift'.
set -- main

while [ "$#" -gt 0 ]
do
        case "$1" in    # Look up the right options for the menu
        main)           OPTIONS="CH1|CH2|CH3|Q" ;;
        submenu1)       OPTIONS="A|B|C|Q"       ;;
        submenu2)       OPTIONS="D|E|F|Q"       ;;
        submenu3)       OPTIONS="X|Y|Z|Q"       ;;
        esac

        PS3=$'\n'"$1 menu: "    # Special variable controlling select prompt

        # Print menu, get reply
        select X in $OPTIONS
        do
                [ -z "$X" ] || break
        done

        # We treat Q specially, it returns to the previous menu.
        if [ "$X" = "Q" ]
        then
                shift           # Return to previous menu
                continue        # Go to top of loop
        fi

        case "$1" in
        main)
                case "$X" in
                CH1)    set -- submenu1 "$*"    ;;
                CH2)    set -- submenu2 "$*"    ;;
                CH3)    set -- submenu3 "$*"    ;;
                esac
                ;;

        submenu1)
                case "$X" in
                A)     # Switch to submenu2 by removing submenu1 before adding
                        shift
                        set -- submenu2 "$*"
                        ;;
                B)      ;;
                C)      ;;
                esac
                ;;

        submenu2)
                case "$X" in
                A)      ;;
                B)      ;;
                C)      ;;
                esac
                ;;

        submenu3)
                case "$X" in
                A)      ;;
                B)      ;;
                C)      ;;
                esac
                ;;

        *)      echo "Unknown menu $1, removing"
                shift
                ;;
        esac
done

echo "Menu list is empty, quitting" >&2

function submenu {
echo "--------------- SUB MENU -------------------"
echo " 1. SUB CH1 "
echo " 2. SUB CH2 "
echo " 3. SUB CH3 "
echo " 4. SUB CH4 "
echo " 5. SUB CH5 "
echo " 6. SUB CH6 "
echo "Choose 1-6"
read subchoice
}
 
function submenu2 {
echo "--------------- SUB MENU 2 -------------------"
echo " 1. SUB2 CH1 "
echo " 2. SUB2 CH2 "
echo " 3. SUB2 CH3 "
echo " 4. SUB2 CH4 "
echo " 5. SUB2 CH5 "
echo " 6. SUB2 CH6 "
echo "Choose 1-6"
read subchoice2
}
 
function submenu3 {
echo "--------------- SUB MENU 3-------------------"
echo " 1. SUB3 CH1 "
echo " 2. SUB3 CH2 "
echo " 3. SUB3 CH3 "
echo " 4. SUB3 CH4 "
echo " 5. SUB3 CH5 "
echo " 6. SUB3 CH6 "
echo "Choose 1-6"
read subchoice3
}