网络编程知识点总结（6）

socket服务端和客户端实现双发聊天

相关函数

（1）socket()函数

int socket(int domain, int type, int protocol);

（2）bind()函数: IP号端口号与相应描述字赋值函数

int bind(int sockfd, const struct sockaddr *addr,socklen t addrlen);

（3）listen()函数:监听设置函数

int listen(int sockfd, int backlog);

（4）accept()函数

int accept(int sockfd, struct sockaddr *addr, socklen t *addrlen);

先写服务端代码：

#include 
#include 
#include 
#include 
#include 
#include 
#include 

int main(int argc,char **argv)
{
        int s_fd;
        int c_fd;
        int n_read;
        char readBuf[128];

        char msg[128] = {0};
        struct sockaddr_in s_addr;
        struct sockaddr_in c_addr;

        if(argc != 3)
        {
                printf("param is not good\n");
                exit(-1);
        }

        memset(&s_addr,0,sizeof(struct sockaddr_in));
        memset(&c_addr,0,sizeof(struct sockaddr_in));
		
        //1.socket
        s_fd = socket(AF_INET,SOCK_STREAM,0);
        if(s_fd == -1)
        {
                perror("socket");
                exit(-1);
        }

        s_addr.sin_family = AF_INET;
        s_addr.sin_port = htons(atoi(argv[2]));
        inet_aton(argv[1],&s_addr.sin_addr);

        //2.bind
        bind(s_fd,(struct sockaddr *)&s_addr,sizeof(struct sockaddr_in));

        //3.listen 
        listen(s_fd,10);

        //4.accept
        int clen = sizeof(struct sockaddr_in);
        while(1)
        {
                c_fd = accept(s_fd,(struct sockaddr *)&c_addr,&clen);
                if(c_fd == -1)
                {
                        perror("accept");
                }
                printf("get connect:%s\n",inet_ntoa(c_addr.sin_addr));

                if(fork() == 0)
                {
                        if(fork() == 0)
                        {
                                while(1)
                                {
                                        memset(msg,0,sizeof(msg));
                                        printf("input:");
                                        gets(msg);
                                        write(c_fd,msg,strlen(msg));
                                }
                        }

                        //5.read
                        while(1)
                        {
                                memset(readBuf,0,sizeof(readBuf));
                                n_read = read(c_fd,readBuf,128);
                                if(n_read == -1)
                                {
                                        perror("read");
                                }
                                else
                                {
                                        printf("get message:%d,%s\n",n_read,readBuf);
                                }
                        }
                        break;
                }
        }
        return 0;
}

再写客户端代码：

#include 
#include 
#include 
#include 
#include 
#include 
#include 

int main(int argc,char **argv)
{
        int c_fd;
        int n_read;
        char readBuf[128];

//      char *msg = "msg form client";
        char msg[128] = {0};
        struct sockaddr_in c_addr;

        memset(&c_addr,0,sizeof(struct sockaddr_in));

        if(argc != 3)
        {
                printf("parm is not good\n");
                exit(-1);
        }
        //1.socket
        c_fd = socket(AF_INET,SOCK_STREAM,0);
        if(c_fd == -1)
        {
                perror("socket");
                exit(-1);
        }

        c_addr.sin_family = AF_INET;
        c_addr.sin_port = htons(atoi(argv[2]));
        inet_aton(argv[1],&c_addr.sin_addr);

        //2.connect
        if(connect(c_fd,(struct sockaddr *)&c_addr,sizeof(struct sockaddr)) == -1)
        {
                perror("connect");
                exit(-1);
        }
        while(1)
        {
                if(fork() == 0)
                {
                        while(1)
                        {
                                memset(msg,0,sizeof(msg));
                                printf("input:");
                                gets(msg);
                                write(c_fd,msg,strlen(msg));
                        }
                }
                while(1)
                {
                        memset(readBuf,0,sizeof(readBuf));
                        n_read = read(c_fd,readBuf,128);
                        if(n_read == -1)
                        {
                                perror("read");
                        }
                        else
                        {
                                printf("get message form server:%d,%s\n",n_read,readBuf);
                        }
                }
        }
        
        return 0;
}       

编译结果：

 实现了双方聊天