Make Bash Scripts Interactive: Animations, GUI Notifications, and Parallel Execution

Display Animation for Long‑Running Tasks

When a Bash script runs a time‑consuming command, a static echo message can be unfriendly; instead you can create a looping ASCII animation using printf with a carriage‑return (\r) to rewrite the current line.

#!/bin/bash
while true; do
    # Frame #1
    printf "\r< Loading..."
    sleep 0.5
    # Frame #2
    printf "\r> Loading..."
    sleep 0.5
done

The script produces an endless two‑frame animation in the terminal.

For a spinner that runs until a background job finishes, use a frame list and kill -0 to poll the job:

#!/bin/bash
sleep 5 &
pid=$!
frames="/ | \\ -"
while kill -0 $pid 2>&1 > /dev/null; do
    for frame in $frames; do
        printf "\r${frame} Loading..."
        sleep 0.5
    done
done
printf "
"

Show Local GUI Notifications from Bash

On GNU/Linux you can call notify-send to pop up a desktop notification:

#!/bin/bash
sleep 10
notify-send "notify.sh" "Task #1 completed"

macOS users can invoke AppleScript via osascript:

#!/bin/bash
sleep 10
osascript -e "display notification \"Task #1 completed\" with title \"notify.sh\""

Multiprocessing in Bash Scripts

Instead of running commands sequentially, define functions and start them in the background with &, then use wait to pause until all finish:

#!/bin/bash
function task1() {
    echo "Running task1..."
    sleep 5
}
function task2() {
    echo "Running task2..."
    sleep 5
}
task1 &
task2 &
wait
echo "All tasks completed"

This reduces total execution time from ~10 seconds to ~5 seconds.

Display GUI Components from Bash

Utilities such as zenity (GNOME) or kdialog (KDE) let Bash scripts open file‑selection dialogs, message boxes, etc. Example:

zenity --file-selection

On macOS the same can be achieved with AppleScript:

osascript -e "POSIX path of (choose file)"

Modernize Terminal Output with Text Styles

Combine tput with echo to apply colors, bold, underline, and italic styles, making messages clearer:

#!/bin/bash
bold=$(tput bold)
underline=$(tput smul)
italic=$(tput sitm)
info=$(tput setaf 2)
error=$(tput setaf 160)
warn=$(tput setaf 214)
reset=$(tput sgr0)

echo "${info}INFO${reset}: This is an ${bold}info${reset} message"
echo "${error}ERROR${reset}: This is an ${underline}error${reset} message"
echo "${warn}WARN${reset}: This is a ${italic}warning${reset} message"

These techniques let developers create more user‑friendly, interactive Bash scripts without needing external GUI frameworks.