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

int my_read(void *, char *, int);

int main(int argc, char *argv[])
{
  FILE *fp;
  char buf[100] = "";

  if (argc < 2) {
    fprintf(stderr, "usage: %s filename\n", argv[0]);
    exit(EXIT_FAILURE);
  }

  fp = fopen(argv[1], "rt");
  if (!fp) {
    perror("fopen");
    exit(EXIT_FAILURE);
  }

  fp->_read = my_read;  /* override NetBSD's read function */
  fread(buf, sizeof(char), 10, fp);
  printf("%s\n", buf);

  fclose(fp);
  return EXIT_SUCCESS;
}

int my_read(void *cookie, char *buf, int n)
{
   return __sread(cookie, buf, n);
}