buf.c

apue第二版每一章节的c语言源码

#include	"ourhdr.h"
void	pr_stdio(const char *, FILE *);
int
main(void)
{
	FILE	*fp;

	fputs("enter any character\n", stdout);
	if (getchar() == EOF)
		err_sys("getchar error");
	fputs("one line to standard 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 error");
	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);
				/* following is nonportable */
	if      (fp->_flag & _IONBF)	printf("unbuffered");
	else if (fp->_flag & _IOLBF)	printf("line buffered");
	else /* if neither of above */	printf("fully buffered");
	printf(", buffer size = %d\n", fp->_bufsiz);
}