From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E83FCDB465 for ; Thu, 12 Oct 2023 00:04:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233754AbjJLAEV (ORCPT ); Wed, 11 Oct 2023 20:04:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231381AbjJLAEU (ORCPT ); Wed, 11 Oct 2023 20:04:20 -0400 Received: from cloud.peff.net (cloud.peff.net [104.130.231.41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C442990 for ; Wed, 11 Oct 2023 17:04:17 -0700 (PDT) Received: (qmail 20833 invoked by uid 109); 12 Oct 2023 00:04:17 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with ESMTP; Thu, 12 Oct 2023 00:04:17 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 11720 invoked by uid 111); 12 Oct 2023 00:04:19 -0000 Received: from coredump.intra.peff.net (HELO coredump.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Wed, 11 Oct 2023 20:04:19 -0400 Authentication-Results: peff.net; auth=none Date: Wed, 11 Oct 2023 20:04:16 -0400 From: Jeff King To: Junio C Hamano Cc: Christoph Anton Mitterer , git@vger.kernel.org Subject: Re: why does git set X in LESS env var? Message-ID: <20231012000416.GA520855@coredump.intra.peff.net> References: <3a2c362c019338ca7408b7a3bc5715b535d15b8a.camel@scientia.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Oct 11, 2023 at 03:23:20PM -0700, Junio C Hamano wrote: > Christoph Anton Mitterer writes: > > > But I still don't get from that why X would be needed? > > > > My less manpage documents it as: > >> -X or --no‐init > >> Disables sending the termcap initialization and deinitialization > >> strings to the terminal. This is sometimes desirable if the > >> deinitialization string does something unnecessary, like clearing > >> the screen. > > > > Is it to avoid clearing the screen? > > I think that was the reason we added it back in 2005. In any case, > asking "why" is not a useful use of anybody's time, because it is > very unlikely to change in the official version we ship, and because > it is so easy for any individual who does not like it to drop by > exporting the $LESS environment variable. I agree it is probably not worth changing now, but I think the history here is a little interesting. Yes, I think "X" was added because less would clear the screen after exiting, and with "F" this meant you'd see nothing. Here's a thread from the same time period discussing it: https://lore.kernel.org/git/cc723f590610210623sbee2075i5f2fd441cceb84ae@mail.gmail.com/ But I also think this was a pretty well-known annoyance with "less" back then. However, I can't seem to reproduce it now! Digging into the history and the changelog, this note is in "changes between less versions 487 and 530": Don't output terminal init sequence if using -F and file fits on one screen. So it seems like the problem has been fixed inside less for recent versions. And in theory we _could_ drop "-X" if it is causing problems. That version of less is ~5 years old. It does seem a little premature to assume everybody has it. And as you say, if there are people who really care about their LESS options, it is easy for them to override it. -Peff