# File src/ruby_supportlib/phusion_passenger/admin_tools.rb, line 28
    def self.tmpdir
      ["PASSENGER_INSTANCE_REGISTRY_DIR", "TMPDIR"].each do |name|
        if ENV.has_key?(name) && !ENV[name].empty?
          return ENV[name]
        end
      end
      return "/var/run/passenger"
    end