a simple spinning animation for your shell scripts

spinner.sh

#!/usr/bin/env bash
#
# a simple spinning animation for your shell scripts

# prints message in front of spinner
# - argument 1: the message to print
spinner_init() {
  printf "$1  "
}

# renders spinner animation once for 0.4 seconds
spinner_spin() {
  printf "\b/"
  sleep 0.1
  printf "\b-"
  sleep 0.1
  printf "\b\\"
  sleep 0.1
  printf "\b|"
  sleep 0.1
}

# prints message after the spinner
# - argument 1: the message to print
spinner_done() {
  printf "\b\b: $1\n"
}

# use it like this
spinner_init "Waiting for demo.txt"
while [ ! -f "./demo.txt" ]; do
  spinner_spin
done
spinner_done "found"