You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: extconf.rb
    path of file: ./repos/tiny_tds/ext/tiny_tds
    
    the code of the file until where you have to start completion: ENV['RC_ARCHS'] = '' if RUBY_PLATFORM =~ /darwin/

# :stopdoc:

require 'mkmf'
req
    
def do_help
  print <<HELP
usage: ruby #{$0} [options]
    --with-freetds-dir=DIR
      Use the freetds library placed under DIR.
HELP
  exit! 0
end