#!/bin/bash
function shutdown() {
   # reset cursor
   tput cnorm
}
trap shutdown EXIT

function spinner() {
   # cursor invisible
   tput civis

   frames='-\|/'
   input=""
   i=0
   while [[ -z $input ]]; do
       read -rsn1 -t 0.1 input

       i=$(( (i+1) %4 ))
       printf "\r${frames:$i:1}"
       sleep .1
   done

   # restore cursor
   tput cnorm
}

spinner