Path: ...!news.misty.com!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail
From: mitchalsup@aol.com (MitchAlsup1)
Newsgroups: comp.arch
Subject: Re: ancient OS history, ARM is sort of channeling the IBM 360
Date: Thu, 27 Jun 2024 17:39:46 +0000
Organization: Rocksolid Light
Message-ID: <3ac7a1edcf37289f8252503ef3cabe7a@www.novabbs.org>
References: <s7r87j1c3u6mim0db3ccbdvknvtjr4anu3@4ax.com> <v5gagi$20gjg$1@dont-email.me> <v5hema$2g2i$2@gal.iecc.com> <v5i0qp$2avln$2@dont-email.me> <v5ifud$tlq$1@gal.iecc.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Info: i2pn2.org;
	logging-data="1380774"; mail-complaints-to="usenet@i2pn2.org";
	posting-account="65wTazMNTleAJDh/pRqmKE7ADni/0wesT78+pyiDW8A";
User-Agent: Rocksolid Light
X-Rslight-Site: $2y$10$ex9Ef/dU097A.c5T8E5LoeNjXzBYz3NCJaJg8q4tgvP/mTlO0riLi
X-Spam-Checker-Version: SpamAssassin 4.0.0
X-Rslight-Posting-User: ac58ceb75ea22753186dae54d967fed894c3dce8
Bytes: 2425
Lines: 34

John Levine wrote:

> According to Lawrence D'Oliveiro  <ldo@nz.invalid>:
>>>>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
>><http://bitsavers.trailing-edge.com/pdf/ibm/360/tss/GC28-2045-1_Time_Sharing_System_PLI_Language_Reference_Manual.pdf>.
>>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.

I did; TSS 360/67 CMU, and I did; both PL/C and PL/1.

> 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