Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/5/84; site othervax.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!think!harvard!seismo!cmcl2!philabs!micomvax!othervax!scott
From: scott@othervax.UUCP (Scott Pace)
Newsgroups: net.lang.c
Subject: Re: c programming style
Message-ID: <427@othervax.UUCP>
Date: Wed, 17-Jul-85 11:37:07 EDT
Article-I.D.: othervax.427
Posted: Wed Jul 17 11:37:07 1985
Date-Received: Sat, 20-Jul-85 09:15:17 EDT
References: <11570@brl-tgr.ARPA> <935@teddy.UUCP>
Reply-To: scott@othervax.UUCP (Scott Pace)
Organization: Philips Information Systems - St. Laurent  P.Q., Canada
Lines: 69

In article <935@teddy.UUCP> rdp@teddy.UUCP (Richard D. Pierce) writes:
>
>One of the points with the C i++ versus i = i = 1 issue is the one of
>pointers (although some alluded to it).
>
>Say we have some item like:
>
>
>	main(argc, argv)
>	int argc;
>	char **argv;
>
>stepping through the array of pointers can be done by by incrementing
>a pointer:
>
>	while (condition) /* or some other loop construct */
>	  . . . 
>
>	  argv++;
>
>This will get us to the next pointer, whereas,
>
>	  argv = argv + 1;
>
>will NOT (unless by the happy happinstance that a pointer is exactly
>the same size as a character!)
>
>The only equivalent "clear" statement would be:
>
>	argv = argv + sizeof(char *); !
>

BULLSHIT!!!

Turn to page 96 of K&R.

Quoted without permission:

"5.4  Address Arithmetic

	If p is a pointer, then p++ increments p to point to the next
element of WHATEVER kind of object p points to, AND p+=i increments p
to point i elements beyond where it currently does."


So if we say i has the value 1;

p++
++p
p+=i

and since p+=i is equivalent to p = p + i

all four forms have EXACLTY the same effect on p.

And in our case:

++argv
argv++
argv+=1
argv=argv+1

are ALL EQUIVALENT!!!

Read the book next time.

Scott Pace, Philips Info. Sys. Ltd., Montreal, Canada

philabs!micomvax!othervax!scott