Re: [RFC] Indicate that Git waits for user input via editor

From: Junio C Hamano <gitster@pobox.com>
Date: Nov 16, 2017, 05:37 UTC
Message-ID: <xmqq375ewzqk.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <xmqq8tf7yxzn.fsf@gitster.mtv.corp.google.com>

Junio C Hamano <gitster@pobox.com> writes:

> I wonder if we can do something like
> ...
> to tentatively give a message without permanently wasting the
> vertical space.

Learning from 13e4760a ("recv_sideband: Do not use ANSI escape sequence on dumb terminals.", 2008-01-08), I think the above should be more like this:

	git_spawn_editor()
	{
		static const char *finish;

		if (!finish) {
			const char ANSI_FINISH[] = "\r\033[K";
			const char DUMB_FINISH[] = "done.\n";
			char *term = getenv("TERM");

			if (term && strcmp(term, "dumb"))
				finish = ANSI_FINISH;
			else
				finish = DUMB_FINISH;
		}

		/* notice the lack of terminating LF */
		fprintf(stderr, "Launched your editor, waiting...");
		fflush(stderr);

		if (!run_command(... spawn the editor ...))
			fputs(finish, stderr);
		else
			fprintf(stderr, "failed (%s)\n", strerror(errno));
		fflush(stderr);
	}