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=-1.0 required=5.0 tests=MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 31960 invoked from network); 17 Dec 2022 00:27:34 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 17 Dec 2022 00:27:34 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id 17D4341C4C; Sat, 17 Dec 2022 10:27:11 +1000 (AEST) Received: from mail.ultimate.com (mail.ultimate.com [104.225.1.121]) by minnie.tuhs.org (Postfix) with ESMTPS id 672AD42413 for ; Sat, 17 Dec 2022 10:27:06 +1000 (AEST) Received: from ultimate.com (localhost [127.0.0.1]) by mail.ultimate.com (8.16.1/8.16.1) with ESMTPS id 2BH0QoMt060199 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO) for ; Fri, 16 Dec 2022 19:26:50 -0500 (EST) (envelope-from phil@ultimate.com) Received: (from phil@localhost) by ultimate.com (8.16.1/8.16.1/Submit) id 2BH0QoH7060198 for tuhs@tuhs.org; Fri, 16 Dec 2022 19:26:50 -0500 (EST) (envelope-from phil) From: Phil Budne Message-Id: <202212170026.2BH0QoH7060198@ultimate.com> Date: Fri, 16 Dec 2022 19:26:50 -0500 To: tuhs@tuhs.org References: <78A69F72-788E-4A31-B750-A39C97F77C75@csp-partnership.co.uk> In-Reply-To: User-Agent: Heirloom mailx 12.4 7/29/08 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID-Hash: GV7NLZSP5GSDRPRXWO4C33VDCCMT3WNS X-Message-ID-Hash: GV7NLZSP5GSDRPRXWO4C33VDCCMT3WNS X-MailFrom: phil@ultimate.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-tuhs.tuhs.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: origin of null-terminated strings List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: > From: Bob Supnik > Tim can comment on the PDP10. MACRO10 (the DEC PDP-10 assembler) had the ASCIZ directive, I don't see it in the May 1964 MACRO6 (PDP-6 assembler) document at: http://bitsavers.trailing-edge.com/pdf/dec/pdp6/F-64MAS_MACRO6_Assembly_Program_May64.pdf Nor the February 1965 version: http://bitsavers.trailing-edge.com/pdf/dec/pdp6/DEC-6-0-TP-MAC-LM-FP-ACT01_MACRO-6_Assembly_Language_Feb65.pdf But it does appear in the May 1965 MACRO-6 manual: http://bitsavers.trailing-edge.com/pdf/dec/pdp6/DEC-6-0-TP-MAC-LM-FP_ACT02_MACRO-6_Assembly_Language_May65.pdf Which has the fullly trifuricated character packings: ASCII/ASCIZ: 7 bit bytes, with the low order bit left over (set at the start of lines in files to indicate a Line Sequence Number metadata for line number based editors) SIXBIT "6-bit ASCII" -- ASCII characters 040 thru 0137 stored as 00 thru 077 in six six bit bytes RADIX50 6 characters from a 40 (050) character character set (plus four flag bits) used to store symbol tables https://en.wikipedia.org/wiki/DEC_RADIX_50#36-bit_systems And ASCIZ is used in listings of the PDP-6 "T.S. Executive" version 1.4 dated 8-18-65: http://bitsavers.trailing-edge.com/pdf/dec/pdp6/tsExec1.4/COMCON.pdf COMCON is "COMmand CONtrol" -- the top level command interpreter built into the monitor (the file name was retained into the later days of TOPS-10), and messages output to the user use ASCIZ directives. And to tie the thread back (closer) to the list subject, the "sub title" headers in the above assembler listing file are "T. HASTINGS 8-2-65" (who I believe is Tom Hastings), which also appears in many other files, including the job scheduler: http://bitsavers.trailing-edge.com/pdf/dec/pdp6/tsExec1.4/CLKCSS.pdf *AND* T. Hastings also appears as an author of the CTSS scheduler: https://softwarehistory.csse.rose-hulman.edu/index.php/ctss-scheduler/ (in the "Full Code" section): :R******TIME SHARING SCHEDULING ALGORITHM*********** :R T. Hastings and R. Daley :R Minor Modifications by G. Schroeder when NEW :R I/O Package Installed....Summer, 1965