# File src/ruby_supportlib/phusion_passenger/loader_shared_helpers.rb, line 164
    def dump_envvars
      if dir = ENV['PASSENGER_DEBUG_DIR']
        File.open("#{dir}/envvars", "wb") do |f|
          ENV.each_pair do |key, value|
            f.puts "#{key} = #{value}"
          end
        end
      end
    rescue SystemCallError
      # Don't care.
    end