/* big_malloc.c  compile with -m64 option */

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

int main(int argc, char *argv[])
{
  char *p;   /* pointer for malloc */
  double *a; /* pointer for calloc */
  int i;
  long gb = 1000000000L;
  long gbx;
  long j;

  printf("big_malloc.c running, 10 malloc and free 1GB \n");
  for(i=0; i<10; i++)
  {
    printf("about to malloc and free 1GB the %d time \n",i+1);
    p = malloc(gb);
    if(p==NULL)
    {
      printf("malloc failed, bye \n");
      exit(1);
    }
    /* write to be sure space is available */
    for(j=0; j<gb; j=j+100) *(p+j) = i;
    free(p);
  }
  gbx = gb+gb;
  printf("about to malloc and free %ld \n", gbx);
    p = malloc(gbx);
    if(p==NULL)
    {
      printf("malloc failed, bye \n");
      exit(1);
    }
    /* write to be sure space is available */
    for(j=0; j<gbx; j=j+1000) *(p+j) = 2;
    free(p);
  gbx = gbx+gb;
  printf("about to malloc and free %ld \n", gbx);
    p = malloc(gbx);
    if(p==NULL)
    {
      printf("malloc failed, bye \n");
      exit(1);
    }
    /* write to be sure space is available */
    for(j=0; j<gbx; j=j+1000) *(p+j) = 3;
    free(p);
  gbx = gbx+gb;
  printf("about to malloc and free %ld \n", gbx);
    p = malloc(gbx);
    if(p==NULL)
    {
      printf("malloc failed, bye \n");
      exit(1);
    }
    /* write to be sure space is available */
    for(j=0; j<gbx; j=j+1000) *(p+j) = 4;
    free(p);
  gbx = gbx+gb;
  printf("about to malloc and free %ld \n", gbx);
    p = malloc(gbx);
    if(p==NULL)
    {
      printf("malloc failed, bye \n");
      exit(1);
    }
    /* write to be sure space is available */
    for(j=0; j<gbx; j=j+1000) *(p+j) = 5;
    free(p);
  gbx = gbx+gb;
  printf("about to malloc and free %ld \n", gbx);
    p = malloc(gbx);
    if(p==NULL)
    {
      printf("malloc failed, bye \n");
      exit(1);
    }
    /* write to be sure space is available */
    for(j=0; j<gbx; j=j+1000) *(p+j) = 6;
    free(p);
  gbx = gbx+gb;
  printf("about to malloc and free %ld \n", gbx);
    p = malloc(gbx);
    if(p==NULL)
    {
      printf("malloc failed, bye \n");
      exit(1);
    }
    /* write to be sure space is available */
    for(j=0; j<gbx; j=j+1000) *(p+j) = 7;
    free(p);
  printf("try calloc on 800000000 items of size 8 6.4GB \n");
    a = calloc(800000000L,8);
    if(p==NULL)
    {
      printf("calloc failed, bye \n");
      exit(1);
    }
    for(j=0; j<800000000L; j=j+1000L) a[j] = 3.5;
    
  printf("successful end big_malloc \n");
  return 0;
} /* end big_malloc */