#!/bin/sh
# inspired by https://www.unix-ninja.com/p/A_cheat-sheet_for_password_crackers

# usage: pw [length [characters]]
tr -dc "${2:-'a-zA-Z0-9._!@#$%^&*()'}" < /dev/urandom \
  | fold -w "${1:-17}" \
  | head -n "${3:-1}"