/*
Try putting
   000
   314
   159
   26 5
    35
into data.txt.
*/

   
#include <stdio.h>

void die_read(void)
{
  fprintf(stderr,"file2: fatal: unable to read data.txt\n");
  exit(111);
}

int main(void)
{
  FILE *f;
  int r;
  int n;

  f = fopen("data.txt","r");
  if (!f) die_read();

  for (;;) {
    r = fscanf(f,"%d",&n);
    if (r < 1) break;
    printf("data.txt has the number %d.\n",n);
  }

  if (ferror(f)) die_read();

  if (r == 0)
    printf("data.txt has something non-numeric.\n");
  else
    printf("End of data.txt.\n");

  return 0;
}