I wanted a simple way to repeat a command purely in Bash: /usr/local/bin/live

live

#!/bin/bash
# A simple script to "watch" a command in pure Bash.

help() {
  echo "live is a simple bash script, that keeps looping a specified command, just like the well known watch command. But made in Bash."
  echo
  echo "  Usage:"
  echo "    live [arguments...] command"
  echo
  echo "  Arguments:"
  echo "    -h  This helpy helper. :)"
  echo "    -dX 'X' being a valid integer/number. 2 by default."
  echo
  echo "  Examples:"
  echo "    live -d5 tree /path/to/directory"
  echo "    live -d 5 tree /path/to/directory"
  echo "    live tree /path/to/directory"
  exit 3
}

usage() {
  echo "Usage: $0 [-d <seconds>] commandtorun [arguments...]" 1>&2;
  echo "Example: $0 -d 5 tree /path/to/directory" 1>&2;
  exit 2;
}

# Defaults
delay=2

while getopts ":d:h?" opt; do
    case "${opt}" in
        h)
            help
            ;;
        d)
            delay=${OPTARG}
            [[ $delay =~ ^-?[0-9]+$ ]] || usage
            ;;
        *)
            usage
            ;;
    esac
done

shift $((OPTIND-1))

while :; do
  clear
  $*
  sleep $delay
done