[clug-progsig] realloc()

[Rob S]

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. 

-Rob.