Re: "less -F" is broken

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Aug 15, 2018, 21:57 UTC
Message-ID: <CA+55aFxjUsvhHwQGthGiLr537BGHkd-LECXVv8KzBTMMCo1bKQ@mail.gmail.com>
In-Reply-To: <87k1orqpxj.fsf@evledraar.gmail.com>

On Wed, Aug 15, 2018 at 2:29 PM Ævar Arnfjörð Bjarmason <avarab@gmail.com> wrote:

Show 7 quoted lines

>
> Downloading & trying versions of it locally reveals that it's as of
> version 520, not 530. The last version before 520 is 487. Presumably
> it's covered by this item in the changelog:
>
>     Don't output terminal init sequence if using -F and file fits on one
>     screen[1]

Side note: that's sad, because we already use X in the default exactly for that reason.

So apparently "less" was broken for us to fix something that we already had long solved. The code basically tried to do "automatic X when F is set".

And all that line_count stuff (which is what breaks) is pointless when -X is already given.

That does give a possible fix: just stop doing the line_count thing if no_init is set.

So "-F" would continue to be broken, but "-FX" would work.

Something like the attached patch, perhaps?

            Linus

 main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/main.c b/main.c
index 179bd78..961a9db 100644
--- a/main.c
+++ b/main.c
@@ -59,6 +59,7 @@ extern int	missing_cap;
 extern int	know_dumb;
 extern int	pr_type;
 extern int	quit_if_one_screen;
+extern int	no_init;
 
 
 /*
@@ -274,7 +275,7 @@ main(argc, argv)
 	{
 		if (edit_stdin())  /* Edit standard input */
 			quit(QUIT_ERROR);
-		if (quit_if_one_screen)
+		if (quit_if_one_screen && !no_init)
 			line_count = get_line_count();
 	} else 
 	{