wait for file change instead of editor exit

Hi
This is a great tool. It would be a bit more great if it would wait for a change in the file instead of waiting for the opened editor to close. Let me explain it: I have redcar open all the time with my project. Now I would like to do ENV["EDITOR"] = "redcar"; ed 'afile.rb', and redcar would start if not started, else open the file if not opened, else select the tab with the file. Then I would edit the file, and save it, but not close redcar. And as redcar forks and I don't close it after editing, interactive_editor would not execute my file. Would be great if that could be solved!