srand(time(NULL))

Can someone please explain to me why the rand() function wont return values in %10. It also doesn't look like the for loop is running the amount of times I want. I want to generate 1000 random numbers and write them to the file, but the print statement outputs around 300 integers.

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

#define ELEMENTS 1000
main()
{
    srand(time(NULL));

    FILE *fp1;
    int num, buffer;

    fp1 = fopen("myFile.bin","wb");


    for(int i=0; i<ELEMENTS; i++)
    {
        num = rand()%1000;

        fwrite(&num, sizeof(int), 1, fp1);
    }//end for

    fclose(fp1);

    fp1 = fopen("myFile.bin", "rb");

    while(feof(fp1)==0)
    {
        fread(&buffer, sizeof(int), 1, fp1);
        printf("\n%d\n",buffer);
    }//end for

    fclose(fp1);
}//end main