Previously we have looked at various ways of making scripts interactive with read and select. You can use the dialog package if you want something a bit fancier.

It allows you to create various dialog boxes from your scripts.

Installation

Ubuntu / Debian

sudo apt install dialog

Arch Linux

sudo pacman -S dialog

Usage

To show a simple message:

dialog --msgbox "Hello World" 6 20

Where 6 and 20 is the height and width of the dialog.

A title can also be set.

dialog --title "Lorem Ipsum" \
  --msgbox "Incidunt ut ullam laudantium. Illum enim accusantium fugit ipsa. Molestiae quia quia sit eaque ut harum. Nemo sunt et cum error doloremque animi aut consequatur." \
  10 40

Notice \ is used escape newline char, so the command can span several lines.

Some of the text is still visible after the dialog has been closed. This can be fixed with the --clear flag.

dialog --title "Lorem Ipsum" --clear \
  --msgbox "Incidunt ut ullam laudantium. Illum enim accusantium fugit ipsa. Molestiae quia quia sit eaque ut harum. Nemo sunt et cum error doloremque animi aut consequatur." \
  10 40

Input

We can also make dialog boxes that allows the user to type input.

dialog --title "Name" --clear --inputbox "Please enter your name:" 10 40

You might be wondering, how you can reference the text that was types into an inputbox. It simply goes to stderr so you can redirect it to a file.

dialog --title "Name" --clear --inputbox "Please enter your name:" 10 40 2> name

Now you got a file named “name” with whatever the user typed. Notice 2> means redirect stderr.

If you don’t want to use any intermediate files, then we can pass --stdout flag.

name=`dialog --stdout --title "Name" --clear --inputbox "Please enter your name:" 10 40`

Yes/No

Great for confirming an action before proceeding.

dialog --title "Proceed" --clear --yesno "Do you really want to proceed?" 10 40

Check the exit code for answer (echo $?) where 0 is “yes” and 1 is “no”.

Other types of boxes

Password

The package supports many different kinds of dialogs. Let’s look at some.

dialog --title "Password" --insecure --clear --passwordbox "Please enter your password for sudo:" 10 40

Or with stars *:

dialog --title "Password" --insecure --clear --passwordbox "Please enter your password for sudo:" 10 40

Menu

dialog --clear --title "You favorite distro" "$@" \
        --menu "What is your favorite Linux distribution?\n\n\
          Choose the distro you like:" 20 50 4 \
        "Ubuntu"  "Very popular" \
        "Mint" "Often recommended to beginners" \
        "Bazzite" "Great for gaming" \
        "Arch Linux" "Simple and customizable" \
        "NixOS" "Unified configuration"

Checklist

dialog --title "Which are fruits?" "$@" \
        --checklist "HR have asked you to identify objects.\n\
Your answer might be used to replace humans with AI.\n\
Press SPACE to toggle an option on/off. \n\n\
  Which of the following are fruits?" 20 61 5 \
        "Apple"  "It's an apple." off \
        "Dog"    "No, that's not my dog." ON \
        "Orange" "Yeah, that's juicy." off \
        "Chicken"    "Normally not a pet." off \
        "Cat"    "No, never put a dog and a cat together!" oN \
        "Fish"   "Cats like fish." On \
        "Lemon"  "You know how it tastes." on

Calendar

dialog --title "Christmas" --clear --calendar "Please choose a date..." 0 0 24 12 2025

File select

dialog --title "Please choose a file" "$@" --fselect "$HOME/" 14 48

For more examples, see “sample” directory in the source code found here.