client2.c

此源码是著名的教材BeginningLinux Programming中文名字叫Linux程序设计书中的源代码

#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <sys/stat.h>


#define BUF_SIZE	256
#define PROJ_ID		32
#define PATH_NAME	"/tmp"
#define SERVER_MSG	1
#define CLIENT_MSG	2

int main(void)
{
	/*用户自定义消息缓冲区*/
	struct mymsgbuf {
		long msgtype;
		char ctrlstring[BUF_SIZE];
	} msgbuffer;
	int	qid; 	/*消息队列标识符*/
	int	msglen;
	key_t	msgkey;

	/*获取键值*/
	if ((msgkey = ftok(PATH_NAME, PROJ_ID)) == -1)
	{
		perror("ftok error!\n");
		exit(1);
	}

	if ((qid = msgget(msgkey, IPC_CREAT|0660)) == -1)
	{
		perror("msgget error!\n");
		exit(1);
	}

	while (1) 
	{
		if (msgrcv(qid,&msgbuffer,BUF_SIZE,SERVER_MSG,0) == -1)
		{
			perror ("Server msgrcv error!\n");
			exit (1);
		}

		printf ("server: %s\n", msgbuffer.ctrlstring);  
		printf ("client: ");
		fgets ( msgbuffer.ctrlstring, BUF_SIZE, stdin);
		if (strncmp ("exit", msgbuffer.ctrlstring, 4) == 0) 
		{
			break;
		}
		msgbuffer.ctrlstring[strlen(msgbuffer. ctrlstring)-1] = '\0';
		msgbuffer.msgtype = CLIENT_MSG;
		if(msgsnd(qid,&msgbuffer,strlen(msgbuffer.ctrlstring) + 1,0) == -1)
		{
			perror("client msgsnd error!\n");
			exit(1);
		}
	}
	exit(0);
}