Path: ...!news.iecc.com!.POSTED.news.iecc.com!not-for-mail From: John Levine Newsgroups: comp.arch Subject: Re: ancient OS history, ARM is sort of channeling the IBM 360 Date: Thu, 27 Jun 2024 01:40:29 -0000 (UTC) Organization: Taughannock Networks Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Date: Thu, 27 Jun 2024 01:40:29 -0000 (UTC) Injection-Info: gal.iecc.com; posting-host="news.iecc.com:2001:470:1f07:1126:0:676f:7373:6970"; logging-data="30394"; mail-complaints-to="abuse@iecc.com" In-Reply-To: Cleverness: some X-Newsreader: trn 4.0-test77 (Sep 1, 2010) Originator: johnl@iecc.com (John Levine) Bytes: 2476 Lines: 36 According to Lawrence D'Oliveiro : >>>possible to request “locate mode”, ... >>>* It only works for reads, not for writes >> >> It works fine for writes on IBM systems. PL/I even has a LOCATE >> statement to get a buffer to write into. > >I found this manual >. >On page 96, it says > > The LOCATE Statement > -------------------- > ... >So it has its own limitations on applicability. For example, it only >seems to work for writes, not reads. Well, yeah. Keep reading and on page 97 you'll find the SET option which is how a you get the pointer for a locate mode READ. It was more common when defining based data to say in the declaration what the default pointer to the data was, so if you said to READ or LOCATE the item, it'd automatically set the pointer. That TSS manual is rather estoteric since hardly anyone ever used TSS and even those of use who did, didn't write much PL/I. Here's the regular PL/I manual which explains locate mode for reading and writing on page 168. https://bitsavers.org/pdf/ibm/360/pli/C28-8201-1_PLIrefMan_Jan69.pdf -- Regards, John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies", Please consider the environment before reading this e-mail. https://jl.ly