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Comment by M9HF8wwiaAdZKEZ | Hacker News Reader

As far as I can tell, this appears to be confusing Ctrl+C (SIGINT, which terminates a process, and is usually not restartable), with Ctrl+Z (SIGTSTP, which pauses a process, and is thus restartable).

The only software I can think of that could "restart" after a Ctrl+C is usually daemons or other long-lived processes (which already need to be able to "restart" after any kind of shutdown and thus have significant amounts of code dedicated to serializing and unserializing their internal state).

TFA even goes so far as to talk about memory leaks - which are completely irrelevant when your process is about to exit anyway!

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This article is quite a roller coaster to get what it is about. As far as I understand it, the author wants SIGINT to become some sort of a universal “cancel” button which may or may not exit a process, because the idea is to stop and rollback to a nearest sensible restart point. E.g. an interactive disk formatting tool may stop lenghty formatting on SIGINT but wouldn’t just exit. It would clean up the mess and return to its menu where e.g. batch configuration happens, so a user doesn’t lose next steps. The author basically wants modern gui features in console via signals.

Yeah, and as others have pointed out already, many existing interactive terminal programs handle SIGINT in this way. E.g. programming language repls interrupt running code and return to the top level prompt. E.g. mutt (SIGINT will cause mutt to politely asks if you want to exit before doing so).

I think of it this way: we have both SIGINT and SIGTERM for a reason. One "interrupts" and the other "terminates" and there are often good reasons to handle "interrupt" differently from "terminate" -- at least in interactive programs.

No, you misread the article.

Open a Ruby interpreter (`irb`). Type `i=0; loop { i += 1 }`. Press Ctrl+C.

* Irb is still running.

* Your infinite loop has been stopped.

Type `i`:

* The REPL state preserved as much progress as it could when you aborted the run.

Now do the same thing in `sh`. Now `python`. Now `psql`. All handle Ctrl+C in the way the article mentioned!

So what is an example of an application that doesn't do this, that you would want to?

> this appears to be confusing Ctrl+C (SIGINT, which terminates a process, and is usually not restartable),

Respectfully, you seem to be confusing SIGINT, which is an interrupt signal and SIGTERM, which is a terminate signal. Many processes interpret SIGINT in a way which is indistinguishable from SIGTERM, but others do not (e.g. most REPLs).

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