fduplex.c

让你了解Unix进程间的通信是如何实现的

#include	"unpipc.h"

int
main(int argc, char **argv)
{
	int		fd[2], n;
	char	c;
	pid_t	childpid;

	Pipe(fd);		/* assumes a full-duplex pipe (e.g., SVR4) */
	if ( (childpid = Fork()) == 0) {		/* child */
		sleep(3);
		if ( (n = Read(fd[0], &c, 1)) != 1)
			err_quit("child: read returned %d", n);
		printf("child read %c\n", c);
		Write(fd[0], "c", 1);
		exit(0);
	}
		/* 4parent */
	Write(fd[1], "p", 1);
	if ( (n = Read(fd[1], &c, 1)) != 1)
		err_quit("parent: read returned %d", n);
	printf("parent read %c\n", c);
	exit(0);
}