The code fragment that the author complains about has an even more serious fault: it doesn’t check for the existence of an `ed.hup` file. If you happen to have

The code fragment that the author complains about has an even more serious fault: it doesn’t check for the existence of an `ed.hup` file. If you happen to have one, because you’re unaware of `ed`’s behavior and you like to give weird names to your files, `ed` will wipe it out when trying to help you. Vim does similar irresponsible things with its backup files¹ in its default configuration. It not only destroys existing files without checking, but prevents many auto-build systems from working correctly. All these behaviors are reckless, especially as there are obvious alternatives that don’t make assumptions about the users' files. [1] https://lee-phillips.org/badvim/ https://lee-phillips.org/badvim/