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Re: Book questions

On Friday 10 April 2015 23:01:14 David Wright wrote:
> Quoting Gene Heskett (gheskett@wdtv.com):
> > On Friday 10 April 2015 10:28:24 Alexis wrote:
> > > Having said that, one thing i always felt was sorely lacking in
> > > K&R was a more thorough description of pointers. However, i feel
> > > that issue has now been addressed by Richard Reese's excellent
> > > "Understanding and Using C Pointers":
> My goodness, I just googled it, clicked on a link, and found I had
> downloaded a copy! Published 2013. Where do they make their money?
> (And do I call it the "Piping Crow Book" or will "Crow Book" do?)
> > That has never been a problem once you understand that a pointer,
> > even to a 3 or 4 dimmensional array of data, is nothing more, nor
> > less, than the address in memory of the first element of that array.
> > ALL other offsets to other elements in that array are calculated,
> > sometimes in the code issued by the compiler, or occasionally in
> > issueing the code to calculate it on the fly.  Not often done as its
> > a huge speed hit when it does that.
> Sigh. You only have to read the first two paragraphs of the reference
> for a contradiction of this:
> "A solid understanding of pointers and the ability to effectively use
> them separates a novice C programmer from a more experienced
> one. Pointers pervade the language and provide much of its
> flexibility. They provide important support for dynamic memory
> allocation, are closely tied to array notation, and, when used to
> point to functions, add another dimension to flow control in a
> program.
> "Pointers have long been a stumbling block in learning C. The basic
> concept of a pointer is simple: it is a variable that stores the
> address of a memory location. The concept, however, quickly becomes
> complicated when we start applying pointer operators and try to
> discern their often cryptic notations. But this does not have to be
> the case. If we start simple and establish a firm foundation, then the
> advanced uses of pointers are not hard to follow and apply."

This part never bothered me, and I did use the pointer as a pointer to a 
function a couple times.  I can't put a finger on it, but that always 
seemd a bit spooky.  But TBT, I think making full use of it would have 
been difficult with the C compiler I was using at the time. But now the 
years have added a considerable layer of rust to the wet ram, so I've 
been using bash scripts here on linux or straight assembly on the 6x09 
machines I have.
> Cheers,
> David.

Cheers, Gene Heskett
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>

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