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=-3.6 required=5.0 tests=MAILING_LIST_MULTI, NICE_REPLY_A autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 15940 invoked from network); 27 Nov 2021 01:10:46 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 27 Nov 2021 01:10:46 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 8CF769CEB5; Sat, 27 Nov 2021 11:10:42 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 0CC4C9CE86; Sat, 27 Nov 2021 11:07:57 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id 592FC9CE5D; Sat, 27 Nov 2021 10:56:41 +1000 (AEST) X-Greylist: delayed 528 seconds by postgrey-1.36 at minnie.tuhs.org; Sat, 27 Nov 2021 10:56:40 AEST Received: from rooster.satexas.com (rooster.satexas.com [207.235.90.2]) by minnie.tuhs.org (Postfix) with ESMTPS id A030894942 for ; Sat, 27 Nov 2021 10:56:40 +1000 (AEST) Received: from localhost (localhost [127.0.0.1]) by rooster.satexas.com (Postfix) with ESMTP id 42ECE1C2A94 for ; Fri, 26 Nov 2021 18:47:51 -0600 (CST) Received: from rooster.satexas.com ([127.0.0.1]) by localhost (rooster.satexas.com [127.0.0.1]) (maiad, port 10024) with ESMTP id 10630-01 for ; Fri, 26 Nov 2021 18:47:50 -0600 (CST) Received: from [192.168.147.220] (rrcs-71-42-153-195.sw.biz.rr.com [71.42.153.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: csauer@nwhillsumc.org) by rooster.satexas.com (Postfix) with ESMTPSA id 494CC1C2AAA for ; Fri, 26 Nov 2021 18:47:50 -0600 (CST) Message-ID: <632335e1-c1ea-0eb8-2629-3e0829057da7@technologists.com> Date: Fri, 26 Nov 2021 18:47:49 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.3.2 Content-Language: en-CA To: tuhs@minnie.tuhs.org References: <0ABB7ECD-049B-4993-938F-82BC924E0F39@gmail.com> <20211127002307.C6E3A2B6CEC@yagi.h-net.msu.edu> <20211127003006.GK19525@mcvoy.com> From: "Charles H. Sauer" In-Reply-To: <20211127003006.GK19525@mcvoy.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: World Net ProMail v2.0.0 Subject: Re: [TUHS] PL/I stuff - was: Book Recommendation X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" I haven't done anything with 9 track tapes for a long time, but I used to help my father with his statistical research, processing what at the time seemed massive census and similar data sets on 9 track tape (using PL/I on 370s at U. MO Columbia). Some of his tapes were quite old, stored in his basement and then his garage, but I don't recall problems reading any of them. IMNSHO, it all depends on the brand/formulation of the tape. I've been going through old audio tapes and digitizing them (https://notes.technologists.com/notes/2021/08/21/making-private-1960s-and-70s-recordings-public/). Some are over 50 years old and still seem as good to me as when they were recorded. Others, I can anticipate from the brand/formulation that they are going to be trouble, if salvageable at all. Most surprisingly, unbranded and similar budget tapes have survived as well or better than some of the high-priced stuff. A few days ago I tried a reel from 1968. I was dismayed by how many times it had been spliced, but replace the splicing tape and found it viable. I have dozens of DDS-2, 3 & 4 cartridges from the 90s that I occasionally try to read. I don't recall any of them failing. (We probably should be COFFing this up.) Charlie On 11/26/2021 6:30 PM, Larry McVoy wrote: > On Fri, Nov 26, 2021 at 07:23:07PM -0500, Dennis Boone wrote: >> > In my experience 9 track tapes were not guaranteed to be readable after >> > some interval. In fact, a standard operations procedure was to copy >> > important tapes to new media periodically. >> >> There are always ways in which your backups can go wrong and not be >> readable, and I'm not arguing that here. >> >> But 9 track tapes have turned out to be pretty spectacularly long-lived. >> I've personally read tapes that were stored for 30+ years in >> unconditioned spaces. > > Contrast that with the write only exabyte tapes. I lost some stuff to those. > -- voice: +1.512.784.7526 e-mail: sauer@technologists.com fax: +1.512.346.5240 Web: https://technologists.com/sauer/ Facebook/Google/Twitter: CharlesHSauer