From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Mikhail Pomaznoy Newsgroups: gmane.emacs.help Subject: Re: Memory-efficient way of opening large files in Emacs read-only Date: Fri, 9 Dec 2022 10:03:15 +0700 Message-ID: References: <8e91d0e8-2474-dd98-9bca-4606becd974d@mikpom.ru> <87sfhqdl7a.fsf@mbork.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="14361"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.5.1 Cc: help-gnu-emacs@gnu.org, fgunbin@fastmail.fm To: Marcin Borkowski Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Dec 09 04:04:09 2022 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p3TgG-0003XE-QG for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 09 Dec 2022 04:04:09 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p3Tfb-0006bF-Bs; Thu, 08 Dec 2022 22:03:27 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p3TfY-0006Z8-BX for help-gnu-emacs@gnu.org; Thu, 08 Dec 2022 22:03:24 -0500 Original-Received: from mikpom.ru ([212.193.52.17]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p3TfV-00082Y-Q7 for help-gnu-emacs@gnu.org; Thu, 08 Dec 2022 22:03:23 -0500 Original-Received: from [192.168.0.101] (nat-88-4.nsk.sibset.net [5.44.169.94]) by mikpom.ru (Postfix) with ESMTPSA id 1EACAF52; Fri, 9 Dec 2022 10:03:16 +0700 (+07) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=mikpom.ru; s=dkim; t=1670554996; bh=JXa/bxysNE5wRZ5Q6/kiOjz6f3tZNJLReDHzrpEg/R4=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=WDWtAdondJiuumusWZAM7WlYQNe6wFtB0VUgSUyb60jous8h7lt7UV9/8jJfB3muG t3LzWYH9CQLMRHBJ0JBGLGOMvudfy3hmCEL3XMdt/0xIv7p290MH/S7pQiR5ovP1Bk P9klFBIJ81R9+DXJjZQh3uzWE778AgGL6BE+FizrK6FRCP5Kf3/HO4ZyLORR/Ye7ro 27ieVqWdsZoIZ36CfN3IraXoGXs1lLT+l1X96WbwMubtuP21liamTaH4+8111llD8s aQ6Z7XBIyrLdiRVJlVO6Fc/X3df0TANmFAj87rFy7Qb1mmMt/bGj+Z0SAHZBk9YlYx 25QsAnwzE2reA== Content-Language: en-US In-Reply-To: <87sfhqdl7a.fsf@mbork.pl> Received-SPF: pass client-ip=212.193.52.17; envelope-from=mikpom@mikpom.ru; helo=mikpom.ru X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.266, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:141488 Archived-At: Thanks for your replies. Seamless less-like viewing in Emacs (not terminals of any kind) is my ultimate goal and I will look into that per Marcin'c suggestion. If it will turn out not fun (too difficult), further investment into VLF makes total sense. Thanks, -Mikhail On 12/8/22 21:27, Marcin Borkowski wrote: > On 2022-12-08, at 03:49, Mikhail Pomaznoy wrote: > >> Greetings! >> >> In my daily workflows I commonly stumble upon a task of peeking into >> a header of a large (sometimes compressed) file. Those files can >> commonly be gigabytes in compressed form so can't fit into >> memory. I was wondering how can this be done in Emacs to leverage its >> search and navigate capabilities? >> >> In a terminal this task is nicely accomplished with `less`, which >> loads file on demand while you scroll (memory-efficiently) and >> automatically detects at least gzip compression. However I am >> struggling to do something similar in Emacs for quite a long time. >> I tried VLF (requires manually switching chunks loaded, encountered >> problems with compression), view-file (loads everything in memory), >> running less in Emacs terminals (I prefer outside-Emacs terminals) but >> for various reasons all this solutions are suboptimal and I usually >> end up with using `less`. >> >> Is there something in Emacs I am missing? Is something like this makes >> sense to develop (I consider to write something for Emacs) ? I am >> using Emacs 28 and maybe in Emacs 29 there are novelties related to >> this issue? > I have no idea if Emacs has anything like this (I doubt), but the way > I'd go about it would be to either leverage `less' inside one of the > Emacs terminals or write some Elisp, colling to things like `gunzip' and > `head' and then putting the result into some buffer. (I think you could > even make it so that scrolling down would load the next portion in the > background, à la modern Web. While I /hate/ this behavior of websites, > here it could actually make sense.) > > Best, >