[clug-progsig] realloc()

[Cade Cairns]

p.s. if you use an editor like vim with syntax highlighting turned on,
it would have highlighted later code such as to indicate there was an
error in your code. you might want to consider looking into using
that, it is an invaluable tool to have!

On Sun, 20 Feb 2005 09:43:39 -0700, Cade Cairns <cairnsc at gmail.com> wrote:
> You are missing a closing ')' character in the second argument of the
> first realloc() call. This affects the code for the rest of the file
> (or until a matching ')' is found), which would have caused the second
> error. You should hvae:
> 
>     ptr = realloc(NULL, ((strlen(array) + 1) * sizeof(char)));
> 
> Alternatively you could remove the first '(' in the second argument
> since it is not needed:
> 
>     ptr = realloc(NULL, (strlen(array) + 1) * sizeof(char));
> 
> On Sat, 19 Feb 2005 20:03:28 -0700, Rob S <rob.s at telus.net> wrote:
> > I've been learning C and I'm having a bit of trouble allocating memory
> > with realloc() in two instances.
> >
> > gcc is rejecting each instance.
> >
> > I'd like to find out the correct useage of realloc() when allocating
> > memory from a null pointer, and to free said memory with realloc() when
> > its not needed anymore.
> >
> > Here's the code i've typed up. I was wondering if the members of the
> > list could look at it and provide some advice?
> >
> > ---
> > #include <stdio.h>
> > #include <stdlib.h>
> > #include <string.h>
> >
> > main()
> > {
> >     char *ptr, array[] = "This is a string.";
> >     int termination;
> >
> >      /* this is where the first problem is. The code is used as its used
> > in the book, but gcc isnt accepting it, and i dont know why. When i try
> > to compile it, gcc spits out: parse error before ';' token. */
> >     ptr = realloc(NULL, ((strlen(array) + 1) * sizeof(char));
> >     if (ptr != NULL)
> >     {
> >         termination = 0;
> >         strcpy(ptr, array);
> >         printf("%s\n", ptr);
> >     /* I think this is where the problem is, but gcc says there's a
> > parse error before "else", two lines ahead. I'm not sure whats going on
> > here either. In the manual i'm following, the code should compile as
> > written. I really dont know whats going on */
> >         ptr = realloc(ptr, 0);
> >     }
> >     else
> >     {
> >        printf("realloc() failed, exiting.\n");
> >        termination = 1;
> >     }
> >
> >     return termination;
> > }
> >
> > -----
> >
> > I havent had any problems with malloc(), calloc() or free(). I'll see if
> > i can find some errata on the text, if there is any still on the net for
> > this book.
> 


-- 
Regards,
Cade Cairns