# File lib/uuid.rb, line 303
303:   def open_lock(mode)
304:     File.open self.class.state_file, mode, self.class.mode do |io|
305:       begin
306:         io.flock File::LOCK_EX
307:         yield io
308:       ensure
309:         io.flock File::LOCK_UN
310:       end
311:     end
312:   end