Re: Code thats out there!

From: jaco v Iterson (
Date: 06/19/95

> On Thu, 15 Jun 1995, Giao H Phan wrote:
> > on wizbits, as an aside to hex, have you guys started using that idea 
> > whereby you could stuff like 80 bits into one var? i heard some bits and 
> > pieces from pythe or fred about some sorta linked long shit or somethin, 
> > i dunno... wonderin anything ever came of that, and if so, what? ;}
> I haven't heard of 'em at all..unless you're talking about a long 
> double.  I know under Borland C's DOS compiler, a long double is 80 bits, 
> but I was under the impression that it wasn't ANSI, portable, or even 
> especially kosher for use in everyday code.  You could also just use an 
> array of long[2] and write an intelligent function-like macro to figure 
> out which long to compare with, but you'll run smack up against word 
> ordering on different machines, as well as the cases where you need to 
> check bits from both elements of the array.
>  _/\_   GU -d H s : g? p5 au- a17 w v- C UL P L 3- E---- N K- W--- M-- V-- po
> / L  \  Y t 5 j-- R G---- tv-- b D B--- e u*(**) h! f !r !n !y+   
> \_ C_/  =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
>   \/    My life as an instruction: xchg   al,al
> I have great faith in fools -- self confidence my friends call it.
> 		-- Edgar Allan Poe
A bitlist can be used. it goes something like:

struct bits {
  unsigned bit1 :1,
  unsigned bit2 :1,
  unsigned bit3 :1

It is ansi but I'm not sure if i got the syntax right.
The :1 means the var is 1 bit long in memory
(it has to be unsigned if it's 1 bit)
It could be :2 too (maybe for syslog1 and syslog2)
You now also can use something like:
if (bits.bit3) {
instead of 
if (GET_BIT(bitvector, 3)) {

If you want to use both systems you can use something like
union bitunion {
  struct bits,
  long int bitvector

(again i'm not sure of the syntax, check your C-book)

This way the struck and the long int ocupy the same space in memory so
if you change the one, the other is changed automaticly (since they are the same)

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