#!/usr/bin/env bash

mod_mem () {
  # Customizable configuration constants
  local -r DEFAULT_PRE=$'\U0001F9E0 '
  local -r DEFAULT_SUF='%'

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

  printf '%b' "${pre}"
  free | awk 'NR == 2 {printf "%3.0f", $3 * 100 / $2}'
  printf '%b' "${suf}"
}