void * calloc ( size_t num, size_t size );

<cstdlib>

Allocate space for array in memory

Allocates a block of memory for an array of num elements, each of them size bytes long, and initializes all its bits to zero.

The effective result is the allocation of an zero-initialized memory block of (num * size) bytes.

Parameters

num

Number of elements to be allocated.

size

Size of elements.

Return Value

Example

/* calloc example */
#include <stdio.h>
#include <stdlib.h>

int main ()
{
  int i,n;
  int * pData;
  printf ("Amount of numbers to be entered: ");
  scanf ("%d",&i);
  pData = (int*) calloc (i,sizeof(int));
  if (pData==NULL) exit (1);
  for (n=0;n<i;n++)
  {
    printf ("Enter number #%d: ",n);
    scanf ("%d",&pData[n]);
  }
  printf ("You have entered: ");
  for (n=0;n<i;n++) printf ("%d ",pData[n]);
  free (pData);
  return 0;
}

This program simply stores numbers and then prints them out. But the number of items it stores can be adapted each time the program is executed because it allocates as much dynamic memory as needed during runtime.

See also