different streams test, works on 3.5.0-generic, 4.6.3 gcc

buf mode

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

void pr_stdio(const char *name, FILE *fp);

int main(void){
  FILE *fp;
  char c;

  fputs("enter any character\n", stdout);

  if((c = getchar()) == EOF)
    err_sys("getchar err");
  printf("charcter is %c", c);
  fputs("one line to stardard error\n", stderr);

  pr_stdio("stdin", stdin);
  pr_stdio("stdout", stdout);
  pr_stdio("stderr", stderr);


  if ((fp = fopen("/etc/motd", "r")) == NULL)
    err_sys("fopen err");
  if (getc(fp) == EOF)
    err_sys("getc error");
  pr_stdio("/etc/motd", fp);
  exit(0);

}
void pr_stdio(const char *name, FILE *fp){
  printf("stream = %s, ", name);

  if (fp -> _IO_file_flags & _IO_UNBUFFERED)
    printf("unbuffered");
  else if (fp -> _IO_file_flags & _IO_LINE_BUF)
    printf("line buffered");
  else
    printf("fully buffered");
    /*
  printf(", buffer size = %d\n",fp -> _IO_buf_end - _IO_buf_base);
  */
  printf(" ,buffer size=%d\n", fp -> _IO_file_flags & _IO_BUFSIZ);
}