From owner-freebsd-questions@freebsd.org Tue Nov 7 18:46:48 2017 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B0E2BE61A5C for ; Tue, 7 Nov 2017 18:46:48 +0000 (UTC) (envelope-from byrnejb@harte-lyne.ca) Received: from inet08.hamilton.harte-lyne.ca (inet08.hamilton.harte-lyne.ca [216.185.71.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "inet08.hamilton.harte-lyne.ca", Issuer "CA_HLL_ISSUER_2016" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 7E4F27FAD9 for ; Tue, 7 Nov 2017 18:46:48 +0000 (UTC) (envelope-from byrnejb@harte-lyne.ca) Received: from localhost (localhost [127.0.0.1]) by inet08.hamilton.harte-lyne.ca (Postfix) with ESMTP id C161A622A3; Tue, 7 Nov 2017 13:46:46 -0500 (EST) X-Virus-Scanned: amavisd-new at harte-lyne.ca Received: from inet08.hamilton.harte-lyne.ca ([127.0.0.1]) by localhost (inet08.hamilton.harte-lyne.ca [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id hY_ElJF5ptQW; Tue, 7 Nov 2017 13:46:44 -0500 (EST) Received: from webmail.harte-lyne.ca (inet04.hamilton.harte-lyne.ca [216.185.71.24]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by inet08.hamilton.harte-lyne.ca (Postfix) with ESMTPSA id F2B6360A67; Tue, 7 Nov 2017 13:46:43 -0500 (EST) Received: from 216.185.71.44 (SquirrelMail authenticated user byrnejb_hll) by webmail.harte-lyne.ca with HTTP; Tue, 7 Nov 2017 13:46:44 -0500 Message-ID: In-Reply-To: <656b08b1-b79d-8e7e-27ec-e39d883f2355@gmx.com> References: <88a59a82-2902-9f63-0a94-bd23b910e7ad@gmx.com> <88b1870184a8810072fe503917cd86be.squirrel@webmail.harte-lyne.ca> <656b08b1-b79d-8e7e-27ec-e39d883f2355@gmx.com> Date: Tue, 7 Nov 2017 13:46:44 -0500 Subject: Re: sed - remove nul lines from file From: "James B. Byrne" To: "Yuri Pankov" Cc: freebsd-questions@freebsd.org Reply-To: byrnejb@harte-lyne.ca User-Agent: SquirrelMail/1.4.22-5.el6 MIME-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Priority: 3 (Normal) Importance: Normal X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Nov 2017 18:46:48 -0000 On Tue, November 7, 2017 13:28, Yuri Pankov wrote: > On Tue, 7 Nov 2017 21:20:40 +0300, Yuri Pankov wrote: >> On Tue, 7 Nov 2017 13:14:08 -0500, James B Byrne Via >> Freebsd-questions >> wrote: >>> >>> On Tue, November 7, 2017 13:03, Yuri Pankov wrote: >>> >>>> >>>> You want /d, not /g, to delete the *lines* which contain NUL >>>> symbols >>>> (that's what your subject line said). >>>> >>> >>> Sigh. Thank you. That works. However, it also deletes any line >>> that >>> has even one NUL in it regardless of the presence of other non-nul >>> characters on the line. >>> >>> What I wish to accomplish is to delete only the lines that are >>> completely nul. I thought that this could be accomplished by >>> prefacing the match sting with the start of line anchor ^ and >>> ending >>> it with the end of line anchor $ but this does not work as I >>> expect. >> >> "[[.NUL.]]" is just a character specified by its collation name, so >> treat as any other ordinary character: >> >> sed -E '/^[[.NUL.]]+$/d' INFILE > OUTFILE >> >> Need extended regexp here for '+' to work. > > > Or, after looking at re_format(7), it could be written using BREs, > your > choice :-) > > sed '/^[[.NUL.]]\{1,\}$/d' > sed '/^[[.NUL.]]\{0,\}$/d' INFILE > OUTFILE Which has no effect. OUTFILE and INFILE remain identical. I get the exact same result from the first invocation as well. Likewise: sed '/^[[.NUL.]]\{1,\}$/d' INFILE > OUTFILE and sed -E '/^[[.NUL.]]+$/d' INFILE > OUTFILE # diff INFILE OUTFILE # # ll INFILE OUTFILE -rw-r--r-- 1 root wheel 61480 Nov 7 13:09 INFILE -rw-r--r-- 1 root wheel 61480 Nov 7 13:38 OUTFILE I had actually tried these combinations, or at least I believe that I tried these, before I wrote. Given the complexity and arcane nature of whatever flavour of RE one is working with I may have transgressed and written them slightly differently. But the examples you provided me with give the results I obtained exactly. -- *** e-Mail is NOT a SECURE channel *** Do NOT transmit sensitive data via e-Mail Do NOT open attachments nor follow links sent by e-Mail James B. Byrne mailto:ByrneJB@Harte-Lyne.ca Harte & Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3