From: "John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Using Pointers ?
Date: Mon, 03 Feb 1997 15:07:37 -0800
Organization: Two pounds of chaos and a pinch of salt
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To: djgpp AT delorie DOT com
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Dim Zegebart wrote:
> 
> //FOO3
> int foo3(TMyType *ptr)
> {
>  //TMyType has fields fld1 and fld2 both int
>  int i,fld1=ptr->fld1,fld2=&ptr->fld2;
                             ^
I assume you forgot to take out that address operator...

>  for (i=0;i<100000;i++)
>   { fld1++; //here may be any expression. ++ just for example
>     fld2--;
>   }
>  ptr->fld1=fld1;
>  ptr->fld2=fld2
>  return(1);
> }

Sorry; I replied too soon.  This last function will not work the way you
want it to.  By assigning ptr->fld1 to fld1, you are making a _copy_ of
that field.  Then when you modify the copy, the original is unchanged. 
This function will probably be faster than the first two (for obvious
reasons), but it won't work.  :)

-- 
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