Get an inventory of the file system...

inventory_fs.rb

#!/usr/bin/env ruby

def compare_filesystem(previous, current)
  previous_inventory = File.open(previous).readlines
  current_inventory = File.open(current).readlines
  
  # puts "The following files have been added:"
  # puts current_inventory - previous_inventory
  # 
  # puts ""
  puts "The following files have been deleted:"
  puts previous_inventory - current_inventory
  
  # puts ""
  # puts "The following files have not been changed:"
  # current_inventory.each do |item|
  #   if previous_inventory.include?(item)
  #     puts item
  #   end
  # end
end

def debug
  counter = 0
  puts "\nDebug:"
  ARGV.each do |arg|
    counter += 1
    puts "\t[#{counter}] Argument: #{arg}"
  end
  puts ""
end

def invalid_arguments
  #abort("Message goes here")
  puts "\n\tUsage:"
  puts "\t    inventoryfs.rb --inventoryfs directory output_filename"
  puts "\t    *** if directory is blank we'll inventory the current directory ***"
  puts "\tor:"
  puts "\t    inventoryfs.rb --comparefs previous_file current_file"
  puts ""
  exit  
end

def inventory_filesystem(output)
  File.open(output, 'w') do |line|
    line.puts Dir.glob('**/*').each.sort
  end
  # line.puts Dir.glob('**/*').each { | file | file.downcase }.sort
end

arg = ARGV[0]

case arg
when '--inventoryfs'
  if ARGV[1] == nil 
    invalid_arguments
  elsif ARGV[2] == nil
    inventory_filesystem(ARGV[1])
  else 
    Dir.chdir(ARGV[1])
    inventory_filesystem(ARGV[2])
  end
when '--comparefs'
  if ARGV[1] != nil and ARGV[2] != nil
    compare_filesystem(ARGV[1], ARGV[2])
  else 
    invalid_arguments
  end
when '--debug'
  debug
else
  invalid_arguments
end