Get docker containers with minimal info

docker.sh

#!/bin/bash

flag=$1

if [ -z "$flag" ]
then
  docker ps --format "table {{.ID}}\t{{.Names}}\t{{.Status}}" | (read -r; printf "%s\n" "$REPLY"; sort -k 3)
  exit
fi

case $flag in
  "-a"|"--all")
    docker ps -a --format "table {{.ID}}\t{{.Names}}\t{{.Status}}" | (read -r; printf "%s\n" "$REPLY"; sort -k 3)
    exit
    ;;
  "-s"|"--stop")
    running_containers=$(docker ps --format "{{.Names}}")
    if [ -z "$running_containers" ]; then
      echo "There are no running containers to stop"
    else
      docker stop $running_containers
      echo "Stopped the running containers"
    fi
    exit
    ;;
  "-h"|"--help")
    printf "%-10s | %s\n" "Flag" "Description"
    printf "%s\n" "-----------|----------------------"
    printf "%-10s | %s\n" "-a, --all" "Display all running and stopped docker containers."
    printf "%-10s | %s\n" "-s, --stop" "Stop all running docker containers."
    printf "%-10s | %s\n" "-h, --help" "Show this help message."
    exit
    ;;
  *)
    echo "Invalid flag specified. Please use -h or --help for help."
    exit 1
    ;;
esac