bash: run multiple commands and show last line of output

gistfile1.txt

#!/bin/bash

TMPDIR="$(mktemp -d)"

cmd_status() {
  local pid=$1
  local cmd=$2
  local log=$3
  if ps h ${PIDS[$cmd_idx]} > /dev/null; then
    echo -e "› \033[32m${cmd}\033[0m" 
  else
    wait $pid
    code=$?
    echo -e "✔ [${code}] \033[90m${cmd}\033[0m" 
  fi
  tail -n10 "${log}" 2>/dev/null
}


SPINNER=("( ●    )" "(  ●   )" "(   ●  )" "(    ● )" "(     ●)" "(    ● )"
         "(   ●  )" "(  ●   )" "( ●    )" "(●     )")
spinner() {
  local i=$1
  i=$(( i % ${#SPINNER[@]} ))
  echo -n "${SPINNER[$i]}"
}

CMDS=(
"ping -c 10 google.com"
"vmstat 1 5" 
"find /usr -type f"
"exit 255" 
)
PIDS=()

cleanup () {
  tput cnorm; 
  # Kill background jobs
  if [[ ${#PIDS[@]} -gt 0 ]]; then
    kill -15 "${PIDS[@]}" > /dev/null 2>&1
    sleep 0.5
    kill -9 "${PIDS[@]}" > /dev/null 2>&1
    echo "KILLED"
  fi
  rm -rf -- "$TMPDIR"
}
trap cleanup SIGINT SIGTERM

# Start the jobs
idx=0
for ((i = 0; i < ${#CMDS[@]}; i++)); do
  ${CMDS[$i]} &> ${TMPDIR}/cmd_${idx}.log & PIDS+=($!)
  idx=$((idx+1))
done

update_loop() {
  tput civis # cursor invisible
  local num_lines=0
  local cnt=0
  local done=0;

  while true; do 
    test ${num_lines} -gt 0 && tput cuu $num_lines

    echo "Running ${idx} commands $(spinner $cnt)"
    num_lines=1
    cnt=$((cnt+1))

    for cmd_idx in $(seq 0 $((idx -1))); do 
      logfile="${TMPDIR}/cmd_$cmd_idx.log"
      output=$(cmd_status "${PIDS[cmd_idx]}" "${CMDS[cmd_idx]}" "${logfile}") 
      output_lines=$(echo "${output}" | wc -l)
      while IFS= read -r line; do
        tput cr; tput el #clear_line
        echo -e "${line}"
      done <<< "${output}"
      num_lines=$((num_lines + output_lines))
    done
    [[ $done == 1 ]] && break
    jobs | grep Run >/dev/null || done=1
    sleep 0.2
  done

  tput cnorm # cursor normal = visible
}

update_loop
cleanup