嵌入式学习-网络编程-Day2

思维导图

tcp通信流程

udp通信流程

作业1

写一个基于TCP协议的客户端来控制RobArm机械臂

代码

#include <myhead.h>
#define SER_PORT 8888
#define SER_IP "192.168.122.71"
#define CLI_PORT 6666
#define CLI_IP "192.168.122.36"int main(int argc, const char *argv[])
{//1.创建套接字int cfd  = socket(AF_INET,SOCK_STREAM,0/*IPPROTO_TCP*/);if(cfd==-1){perror("socket error");return -1;}printf("cfd=%d\n",cfd);//将端口号快速重用函数int reuse =1;if(setsockopt(cfd,SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse))==-1){perror("setsockopt error");return -1;}//2.绑定（随意）struct sockaddr_in cin;cin.sin_family=AF_INET;cin.sin_port=htons(CLI_PORT);cin.sin_addr.s_addr=inet_addr(CLI_IP);if(bind(cfd,(struct sockaddr*)&cin,sizeof(cin))==-1){perror("bind error");return -1;}printf("bind success");//printf("bind success %s %s %d\n",__FILE__,__func__,__LINE__);//3.连接服务器//3.1填充地址信息结构体struct sockaddr_in sin;sin.sin_family=AF_INET;sin.sin_port=htons(SER_PORT);sin.sin_addr.s_addr=inet_addr(SER_IP);//3.2链接if(connect(cfd,(struct sockaddr*)&sin,sizeof(sin))==-1){perror("connect error");return -1;}printf("链接成功\n");//4.收发数据char bufred[5]={0xff,0x02,0x00,-90,0xff};char bufblue[5]={0xff,0x02,0x01,0,0xff};while(1){char ch;printf("请输入w&a&s&d:");scanf("%c",&ch);getchar();if(ch == 'w'){bufred[3]+=5;if(bufred[3]>90){bufred[3]=90;continue;}}else if(ch == 's'){bufred[3]-=5;if(bufred[3]<-90){bufred[3]=-90;continue;}}else if(ch == 'a'){bufblue[3]-=5;if(bufblue[3]<0){bufblue[3]=0;continue;}}else if(ch == 'd'){bufblue[3]+=5;if(bufblue[3]>180){bufblue[3]=180;continue;}}else{puts("输入有误");}//发送给服务器send(cfd,bufred,sizeof(bufred),0);send(cfd,bufblue,sizeof(bufblue),0);printf("发送成功\n");}//5.关闭套接字close(cfd);return 0;
}

实现结果如下

作业2

再次完成TCP网络通信

代码

#include <myhead.h>
#define SER_PORT 8888
#define SER_IP "192.168.122.36"int main(int argc, const char *argv[])
{//1.创建套接字int sfd  = socket(AF_INET,SOCK_STREAM,0/*IPPROTO_TCP*/);if(sfd==-1){perror("socket error");return -1;}printf("sfd=%d\n",sfd);//将端口号快速重用函数int reuse =1;if(setsockopt(sfd,SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse))==-1){perror("setsockopt error");return -1;}printf("端口号快速重用成功\n");//2.给套接字绑定IP和端口号//2.1填充地址信息结构体struct sockaddr_in sin;sin.sin_family=AF_INET;sin.sin_port=htons(SER_PORT);sin.sin_addr.s_addr=inet_addr(SER_IP);//2.2绑定if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin))==-1){perror("bind error");return -1;}printf("bind success %s %s %d\n",__FILE__,__func__,__LINE__);//3.将套接字设置成监听状态if(listen(sfd,128)==-1){perror("listen error");return -1;}printf("listen success %s %s %d\n",__FILE__,__func__,__LINE__);//4.阻塞等待客户端的链接请求//4.1定义容器接收客户端的地址信息struct sockaddr_in cin;   //用于接收地址信息socklen_t socklen = sizeof(cin);  //用于接收地址信息的大小int newfd=-1;if((newfd =accept(sfd,(struct sockaddr*)&cin,&socklen))==-1){perror("accept error");return -1;}printf("您有一个新的客户端[%s:%d]发来连接请求 success %s %s %d\n",\inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),__FILE__,__func__,__LINE__);//5.跟客户端进行通信char buf[128]="";while(1){bzero(buf,sizeof(buf));int res=recv(newfd,buf,sizeof(buf),0);if(res==0){puts("客户端已经下线");break;}printf("[%s:%d] : %s\n",inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),buf);//给客户端发送消息strcat(buf,"=-=");send(newfd,buf,sizeof(buf),0);printf("发送成功\n");}//6.关闭套接字close(newfd);close(sfd);return 0;
}

#include <myhead.h>
#define SER_PORT 8888
#define SER_IP "192.168.122.36"
#define CLI_PORT 6666
#define CLI_IP "192.168.122.36"int main(int argc, const char *argv[])
{//1.创建套接字int cfd  = socket(AF_INET,SOCK_STREAM,0/*IPPROTO_TCP*/);if(cfd==-1){perror("socket error");return -1;}printf("cfd=%d\n",cfd);//2.绑定（随意）struct sockaddr_in cin;cin.sin_family=AF_INET;cin.sin_port=htons(CLI_PORT);cin.sin_addr.s_addr=inet_addr(CLI_IP);if(bind(cfd,(struct sockaddr*)&cin,sizeof(cin))==-1){perror("bind error");return -1;}printf("bind success %s %s %d\n",__FILE__,__func__,__LINE__);//3.连接服务器//3.1填充地址信息结构体struct sockaddr_in sin;sin.sin_family=AF_INET;sin.sin_port=htons(SER_PORT);sin.sin_addr.s_addr=inet_addr(SER_IP);//3.2链接if(connect(cfd,(struct sockaddr*)&sin,sizeof(sin))==-1){perror("");return -1;}printf("链接成功\n");//4.收发数据char buf[128]="";while(1){bzero(buf,sizeof(buf));printf("请输入:");fgets(buf,sizeof(buf),stdin);buf[strlen(buf)-1]=0;//发送给服务器send(cfd,buf,sizeof(buf),0);printf("发送成功\n");if(strcmp(buf,"quit")==0){break;}//接收服务器发来的消息recv(cfd,buf,sizeof(buf),0);printf("[%s:%d]:%s\n",SER_IP,SER_PORT,buf);}//5.关闭套接字close(cfd);return 0;
}