Example (malloc --Reserve Storage Block)

This example prompts for the number of array entries you want and then reserves enough space in storage for the entries. If malloc was successful, the example assigns values to the entries and prints out each entry; otherwise, it prints out an error.

    #include <stdio.h>
    #include <stdlib.h>

    int main(void)
    {
      long * array;    /* start of the array */
      long * index;    /* index variable     */
      int    i;        /* index variable     */
      int  num;        /* number of entries of the array */

      printf( "Enter the size of the array\n" );
      scanf( "%i", &num );

      /* allocate num entries */
      if ( (index = array = (long *) malloc( num * sizeof( long ))) != NULL )
      {

        for ( i = 0; i < num; ++i )           /* put values in array    */
           *index++ = i;                      /* using pointer notation */

        for ( i = 0; i < num; ++i )           /* print the array out    */
          printf( "array[ %i ] = %i\n", i, array[i] );
      }
      else { /* malloc error */
        perror( "Out of storage" );
        abort();
      }
      return 0;

      /************************************************************************
         The output should be similar to:

         Enter the size of the array
         5
         array [ 0 ] = 0
         array [ 1 ] = 1
         array [ 2 ] = 2
         array [ 3 ] = 3
         array [ 4 ] = 4
      ************************************************************************/
    }