<<Anchor(faq115)>>
== How do I make a menu? ==
Some people like to use `select` because it's simple.  If your own needs are extremely simple, then this may be sufficient for you.  If you want your own look and feel, you can simply write a menu yourself.  There is also [[BashFAQ/040|dialog]], which we won't cover on this page.

=== Using select ===
To use `select`, you need a list of choices.  `select` will automatically assign numbers to the choices, and issue a prompt.  You may customize the prompt.

{{{
$ PS3='¿Qué es más macho? '
$ select ch in schoolbus lightbulb; do echo "You have chosen $ch!"; break; done
1) schoolbus
2) lightbulb
¿Qué es más macho? 45
You have chosen !
$ select ch in schoolbus lightbulb; do echo "You have chosen $ch!"; break; done
1) schoolbus
2) lightbulb
¿Qué es más macho? 2
You have chosen lightbulb!
}}}

If you check for an "empty" (invalid) selection inside the loop, then it becomes slightly less horrible:

{{{
$ select ch in schoolbus lightbulb; do if [[ $ch ]]; then echo "You have chosen $ch!"; break; fi; done
1) schoolbus
2) lightbulb
¿Qué es más macho? 45
¿Qué es más macho? 0
¿Qué es más macho? 2
You have chosen lightbulb!
}}}

And that's `select`.  Moving on....

=== Writing your own menu ===

Just make a loop using `echo` and `read`.  It's really that simple.  Let's spice it up by making a multi-level menu ''application'' instead.

{{{#!highlight bash
#!/bin/bash

main() {
  while true; do
    echo "== Make your selection:"
    echo "a) add"
    echo "s) subtract"
    echo "m) multiply"
    echo "q) quit"
    while true; do
      read -r -n1 -p "> " ch
      echo
      case $ch in
        a) add; break;;
        s) subtract; break;;
        m) multiply; break;;
        q) exit 0;;
        *) echo "Unrecognized command.  Please try again.";;
      esac
    done
  done
}

add() {
  local a b
  while true; do
    echo "== Addition"
    echo "Enter first addend, or q to return to main menu."
    read -r -p "> " a
    [[ $a = q ]] && return
    echo "Enter second addend."
    read -r -p "> " b
    echo "$a + $b = $((a + b))"
  done
}

# subtract and multiply functions not shown

main
}}}

You can make it as simple or as complex as you like.  You can create your own input function to wrap `read` and persist until the user types a syntactically valid response.  You can use `read -e` to allow the user to use readline editing features.  It's all up to you.