On 12/16/22 16:02, Warner Losh wrote:
On Fri, Dec 16, 2022, 1:12 PM Dave Horsfall <dave@horsfall.org> wrote:
On Fri, 16 Dec 2022, Dr Iain Maoileoin wrote:

> I remember running into a .asciz directive n the 70s “somewhere”. It was
> an assembler directive in one of the RT11 systems??? or perhaps the unix
> bootstrap and/or “.s” files - when I get some time I will go read some
> old code/manuals.

MACRO-11 on RSX-11D seems to ring a bell...

I first encountered it on RSTS/E 6C in the MACRO-11 it had... But the v6 macro assembler from DEC via Harvard that eventually wound up in 2BSD is older and dates to 1977 or so.

Warner

The PDP-10 manual I spoke of is from 1971, and there were older editions. For the PDP-7, this manual from 1965, http://www.bitsavers.org/pdf/dec/pdp7/PDP-7_AsmMan.pdf, printed pages 38-40, does not mention "ASCIZ" specifically, but talks about assembler directives "TELETYPE" and "ANALEX" that add a "termination code" of 00 octal, for characters.

DEC also used SIXBIT, a truncated ASCII code that had printing characters but no control characters, so no newline, etc. In that scheme, 00 octal was SPACE. Table here: https://en.wikipedia.org/wiki/Six-bit_character_code#Examples_of_six-bit_ASCII_variants.

Dan H