allocate « pointer « C Array Q&A

1. array of pointers allocation    stackoverflow.com

typedef struct
{
  struct table **symbols; // array of the stack
  int top; //index of the top element
  int size; //maximum size of the stack
}stack;

void *createStack(int size)
{
  stack ...

2. C - allocating an array of pointers, and usage - typecast safety    stackoverflow.com

I'm working with some legacy code that makes extensive use of this kind of thing:

// Allocate a look-up-table of pointers.
long *pointerLUT = (long *) malloc(sizeof(long) * numPointers);

...


// Populate the array with ...

3. C99: Will arrays or heap-allocated buffers ever end at UINTPTR_MAX?    stackoverflow.com

Can I assume the following invariant?

void foo(char *buf, size_t len) {
  // "buf" points to either an array or memory allocated with malloc().
  assert((uintptr_t)(buf + len) < UINTPTR_MAX);
}

4. Fix the bug by returning a pointer to an array allocated on the free store(heap)??    bytes.com

In int* createAndFillArray() you return a pointer to a local variable. That variable will be on the stack (in most platforms) and will be deleted when the function exits so you return a pointer to an object that has been deallocated. As soon as you use the pointer to undefined behaviour is invoked and things can start going wrong. int* createAndFillArray() ...

5. Allocating a double pointer as an array    cboard.cprogramming.com

struct set { int filled; int size; char **data; }; struct set *createSet(int maxElts) { struct set *sp; if ((sp=malloc(sizeof(struct set)))==NULL) { printf("Failed to allocate memory!\n"); abort(); } sp->filled=0; sp->size=maxElts; if ((sp->data=malloc(sizeof(char *)*maxElts))==NULL) { printf("Failed to allocate memory!\n"); abort(); } if (sp->data[0]==NULL) //I wanted this to be allocated in such a way that I could use it as an array at ...

6. Dynamicly allocating an array of pointers    cboard.cprogramming.com