Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!mauxci!eci386!ecicrl!clewis
From: clewis@ferret.ocunix.on.ca (Chris Lewis)
Newsgroups: comp.unix.programmer
Subject: Re: "wobble" in Floating Point (LONG) (was Re: comp_t)
Keywords: Accounting, comp_t, funny floats...
Message-ID: <2069@ecicrl.ocunix.on.ca>
Date: 25 May 91 19:26:50 GMT
References: <512@eskimo.celestial.com> <9105060921.aa11316@art-sy.detroit.mi.us> <599@eskimo.celestial.com> <9105180923.aa03879@art-sy.detroit.mi.us> <13576@dog.ee.lbl.gov>
Organization: Elegant Communications Inc., Ottawa, Canada
Lines: 23

In article <13576@dog.ee.lbl.gov> torek@elf.ee.lbl.gov (Chris Torek) writes:
>In article <9105180923.aa03879@art-sy.detroit.mi.us>
>chap@art-sy.detroit.mi.us (j chapman flack) writes:
>>Of course, the AT&T folks just traded off wobble for storage size and
>>dynamic range. ... Now if they put all of that thought into the DESIGN,
>>why couldn't they have put some of it into the COMMENTS ??
>
>The comp_t stuff appears in 32V Unix (the original VAX port, swapping-
>only) and hence must date back to pre-V7 times.  (32V apparently split
>off just slightly before the V7 release.)

It was certainly in V7 - it was mostly used, I believe, in the "sa" (shell accounting,
aka "process accounting" - not the same as current SV) stuff.  The process accounting
tended to generate big files, so I think they used this compressed form to
save space, and to avoid having to do full floating point as part of the kernel's
duties (of course, tho, the kernel often had to emulate floats and doubles for
user programs if there was no hardware floating point).  Can't remember whether
it was in V6 or not.
-- 
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