#!/bin/bash

mod_cpu () {
  # Customizable configuration constants
  local -r DEFAULT_PRE=' '
  local -r DEFAULT_SUF=''

  local -r pre="${1-${DEFAULT_PRE}}"
  local -r suf="${2-${DEFAULT_SUF}}"

  printf '%b' "${pre}"
  ps --no-headers -A -o %cpu | awk '{cpu = cpu + $1} END {printf "%3.0f", cpu}'
  printf '%b' "${suf}"
}