From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 5484 invoked from network); 1 Mar 2023 16:57:16 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 1 Mar 2023 16:57:16 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id 1B04C4333B; Thu, 2 Mar 2023 02:57:13 +1000 (AEST) Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) by minnie.tuhs.org (Postfix) with ESMTPS id 539A943337 for ; Thu, 2 Mar 2023 02:57:05 +1000 (AEST) Received: from cwcc.thunk.org (pool-173-48-120-46.bstnma.fios.verizon.net [173.48.120.46]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 321Gv1B4031388 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 1 Mar 2023 11:57:02 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mit.edu; s=outgoing; t=1677689822; bh=5F1MTmDG9TQtecxqiL0chJK1Ziya357tsNhl0QW0Y7w=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Wi3kFe20/Dmhnyetc8x1gZXfisOvO4XtJMEiGg3D2ggbvnTe5cdcYsz+EAr/DyTA+ smufziAu/UlMj/ID+qiAo9QwXEq7WcD+3VbI9WK9PTLbXmtCw6acEhsaoLlX+9dqEU oWdMWBgf55YcEK6CjDVKsBuXtMipKMU6LJrr9N7wFPbVls1tljPfZnbDFGxv9DSPp1 ZzqaHxcDsFyGkvnBf8jCxyUnf8IyKTAwMmi39OEvOApFRJUwWmmek0BvgoaKuJCsKq YJG33Jq4kD1ydRdz9/OEbJ5XhG3xk6S1SIoQQ613bnvi72x08Z5ReBnnOBdo160HeH sIA4Sa3UVw/aA== Received: by cwcc.thunk.org (Postfix, from userid 15806) id 74CB915C3593; Wed, 1 Mar 2023 11:57:01 -0500 (EST) Date: Wed, 1 Mar 2023 11:57:01 -0500 From: "Theodore Ts'o" To: Noel Chiappa Message-ID: References: <20230301150905.AA4CD18C07B@mercury.lcs.mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230301150905.AA4CD18C07B@mercury.lcs.mit.edu> Message-ID-Hash: TSQ3D6DNESFCIQZXE6JDSLWHZ4ND2JD5 X-Message-ID-Hash: TSQ3D6DNESFCIQZXE6JDSLWHZ4ND2JD5 X-MailFrom: tytso@mit.edu X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: tuhs@tuhs.org X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: Unix v7 icheck dup problem List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Wed, Mar 01, 2023 at 10:09:05AM -0500, Noel Chiappa wrote: > To do it, you need to i) understand how the FS works (see: > > https://minnie.tuhs.org/cgi-bin/utree.pl?file=V6/usr/man/man5/fs.5 > > but it's pretty simple); ii) understand what the few tools (dcheck; icheck; > clri) do; iii) dive in. In honor of dcheck, icheck, and clri, when I creating debugfs(8) for ext2/ext3/ext4 file system, I implemented the dcheck, icheck, and clri commands. I've been known to use them (and other debugfs commands) from time to time when someone needs emergency data recovery (say, someone who has ten years of Ph.D. research without ever doing backups, and then the file system get scrambled --- although some have argued that if someone doesn't do backups of their research data, maybe they don't *deserve* to get their Ph.D. :-) - Ted