rcvmsg.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 <stdlib.h>
#include <sys/ipc.h>
#include <sys/msg.h>

#define BUF_SIZE	256
#define PROJ_ID		32
#define PATH_NAME	"."

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);
	}

	/*获取消息队列标识符*/
	if((qid = msgget(msgkey, IPC_CREAT|0660)) == -1)
	{
		perror ("msgget error!\n");
		exit (1);
	}

	msglen = sizeof(struct mymsgbuf) - 4;
	if (msgrcv(qid, &msgbuffer, msglen, 3, 0) == -1)  /*读取数据*/
	{
		perror ("msgrcv error!\n");
		exit (1);
	}
	printf("Get message %s\n", msgbuffer.ctrlstring);

	exit(0);
}