Path: utzoo!attcan!uunet!cs.utexas.edu!sun-barr!apple!oliveb!tymix!antares!doctor!jms
From: jms@doctor.Tymnet.COM (Joe Smith)
Newsgroups: comp.sys.misc
Subject: Re: binary data files
Message-ID: <206@doctor.Tymnet.COM>
Date: 16 May 89 01:31:25 GMT
References: <10946@bloom-beacon.MIT.EDU> <225800167@uxe.cso.uiuc.edu> <1970@dataio.Data-IO.COM> <4122@ficc.uu.net>
Reply-To: jms@doctor.Tymnet.COM (Joe Smith)
Organization: McDonnell Douglas Field Service Co, San Jose CA
Lines: 39

In article <4122@ficc.uu.net> peter@ficc.uu.net (Peter da Silva) writes:
>In article <1970@dataio.Data-IO.COM>, bright@Data-IO.COM (Walter Bright) writes:
>> And CPM is based on DEC's RT-11 for PDP-11 computers. At the time, DEC
>> operating systems were very popular, and they all used the \r and \n
>> convention.
>
>That's funny... most DEC systems I know (including RSX, which is what CP/M
   I have to disagree with this statement ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>seems most closely modelled on) store files as a series of variable length
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>records containing (usually) a 2 or 4 byte header containing the length and
>maybe the line number and then the data on the line.
>
>CP/M was actully based directly on an obscure intel DOS called Isis, with
>some teminology (PIP, etc) borrowed from DEC.
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^    agreed
>Peter da Silva, Xenix Support, Ferranti International Controls Corporation.

TOPS-10, TOPS-20, OS/8, RT11, RSTS all use CR+LF.
Only 2 systems, RSX and VMS use variable length records.

History: The PDP-6 evolved into the PDP-10 which runs TOPS-10.  Between the
PDP-6 and the PDP-11 the PDP-8 was invented, running OS/8.  Then came the
PDP-11.  RT-11 looks very much like TOPS-10 scaled down for a single user.
RSTS-11 is a multiuser system that originally had the system utilities
written in interpreted BASIC.  Then came RSX, which uses RMS (Record Management
System) for variable length records without CRLF.  Based on what came before
RSX, I'd say CP/M was NOT based on RSX.

When you count the number of different _Operating_Systems_ DEC has, the
majority use CR+LF.  However, the count of installed systems that use an OS
with RMS is a different story.

This whole topic is irrelevant anyway!  :-)
-- 
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