mainfifo.c

UNIX网络编程 第2卷 进程间通信 代码

#include	"unpipc.h"

#define	FIFO1	"/tmp/fifo.1"
#define	FIFO2	"/tmp/fifo.2"

void	client(int, int), server(int, int);

int
main(int argc, char **argv)
{
	int		readfd, writefd;
	pid_t	childpid;

		/* 4Create two FIFOs; OK if they already exist */
	if ((mkfifo(FIFO1, FILE_MODE) < 0) && (errno != EEXIST))
		err_sys("can't create %s", FIFO1);
	if ((mkfifo(FIFO2, FILE_MODE) < 0) && (errno != EEXIST)) {
		unlink(FIFO1);
		err_sys("can't create %s", FIFO2);
	}

	if ( (childpid = Fork()) > 0) {		/* parent */
		writefd = Open(FIFO1, O_WRONLY, 0);
		readfd = Open(FIFO2, O_RDONLY, 0);

		client(readfd, writefd);

		Waitpid(childpid, NULL, 0);		/* wait for child to terminate */

		Close(readfd);
		Close(writefd);

		Unlink(FIFO1);
		Unlink(FIFO2);
		exit(0);

	}
		/* 4child */
	readfd = Open(FIFO1, O_RDONLY, 0);
	writefd = Open(FIFO2, O_WRONLY, 0);

	server(readfd, writefd);
	exit(0);
}