OpenEuphoria

Re: realloc() failing under DOS (why it does'nt ...)

• Posted by pseudonomus at yahoo.com Nov 08, 2001
• 479 views

--- Robert Craig <rds at RapidEuphoria.com> wrote:
> 
> pseudonomus writes:
> >       s = (char*)Realloc(s, i);
> >       s[i-1] = 'X';
> >       s[i] = 0; /* EOS */
> 
> In C, if s is a pointer to i bytes, then s[i] is
> *not* a valid element.
> The subscripts run from 0 to i-1. You are writing a
> byte beyond
> the allocated space. Sometimes this won't matter.
> Other times
> it will lead to disaster.

Arrghh!
That's a syntax error :p
I posted the C code in question as a quick explenation
of my point, yet I introduced a syntax error in the
proccess.

The code I've being having trouble with is the
following;

char *characterWeld(char *dest,char source)
{
	int dl = strlen(dest);

	dest = (char*)realloc(dest,dl+2);

	dest[dl] = source;
	dest[dl+1] = 0;
	
	return dest;
}

main()
{
   int i = 6000000;
   char *s = (char*)malloc(1);
   while(i--)
       s = characterWeld(s,'X'); /* Fails */
}

Above code is correct for a change :p

But ...

> Buy the source in 2 weeks and learn
> all 
> the tricks of the trade.   

I'll do just that.

> Regards,
>    Rob Craig
>    Rapid Deployment Software
>    http://www.RapidEuphoria.com