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#include <stdlib.h>

void *calloc (
  unsigned int num,    /* number of items */
  unsigned int len);   /* length of each item */

The calloc function allocates memory for an array of num elements. Each element in the array occupies len bytes and is initialized to 0. The total number of bytes of memory allocated is num * len.


  • Source code for this routine is provide in the LIB folder. You may modify the source to customize this function for your particular hardware environment.
Return Value

The calloc function returns a pointer to the allocated memory or a null pointer if the memory allocation request cannot be satisfied.

See Also

free, init_mempool, malloc, realloc

#include <stdlib.h>
#include <stdio.h> /* for printf */

void tst_calloc (void) {
  int *p; /* ptr to array of 100 ints */

  p = calloc (100, sizeof (int));

  if (p == 0)
    printf ("Error allocating array\n");
    printf ("Array address is %p\n", (void *) p);

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