"wobble" in Floating Point (LONG) (was Re: comp_t)

[Chris Lewis]

In article <13576 at dog.ee.lbl.gov> torek at elf.ee.lbl.gov (Chris Torek) writes:
>In article <9105180923.aa03879 at art-sy.detroit.mi.us>
>chap at 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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