Linux--共享队列1

r囧r小猫 2022-07-14 07:50 58阅读 0赞

#include "apue.h"
    
    struct msgbuf
    {
    	long type;
    	char voltage[128];
    	char ID[4];
    };
    
    main(){
    	int id;
    	struct msgbuf sendbuf,readbuf;
    	//创建共享队列
    	id=msgget(IPC_PRIVATE,0777);
    	if(id<0){
    		printf("fail to create share msg  \n");
    	}else{
    		    printf("success to create share msg   id=%d\n",id);
    		    
    		    sendbuf.type = 100;
    		//	strcpy(sendbuf.voltage,"hello liupan");
    			fgets(sendbuf.voltage,128,stdin);
    			//发送消息 第四个参数表示以阻塞的方式写
    		    msgsnd(id,(void *)&sendbuf,strlen(sendbuf.voltage),0);
    		    system("ipcs -q");
    			
    			//第一次读取消息
    			memset(readbuf.voltage,0,sizeof(readbuf.voltage));
    			//100表示数据类型 128表示要读取的数据的大小 第四个表示以阻塞的方式读取
    			//返回值 实际读取到的字节数
    			int re_msg_size = msgrcv(id,(void *)&readbuf,128,100,0);
    			printf(" at first size of read data is %d  readbuf = %s \n",re_msg_size,readbuf.voltage);
    			
    			//再次读取消息
    			memset(readbuf.voltage,0,sizeof(readbuf.voltage));
    			//100表示数据类型 128表示要读取的数据的大小 第四个表示以阻塞的方式读取
    			//返回值 实际读取到的字节数
    			printf(" start to read data at second \n");
    			system("ipcs -q");
    		     re_msg_size = msgrcv(id,(void *)&readbuf,128,100,0); //第二次在读数据已经没有数据了 阻塞
    			printf(" at second size of read data is %d  readbuf = %s \n",re_msg_size,readbuf.voltage);
    			
    			printf(" start to delete share msg===\n");
    			int re_msg=msgctl(id,IPC_RMID,NULL);//删除创建的共享队列
    			if(re_msg<0){
    				perror("");
    				return -1;
    			}
    			printf("success to delete msg \n");
    			system("ipcs -q");
    		
    	}
    	return 0;
    }