Linux环境下用TCP协议写的通信_linux通过tcp和rfid读写器建立通信-优快云博客

本文通过两个C语言程序实例展示了如何实现基本的网络通信。一个程序作为服务器接收来自客户端的数据，另一个程序则作为客户端发送数据到服务器。文章通过具体代码介绍了socket编程的基本用法，包括socket创建、绑定、监听、接受连接请求以及数据收发等关键步骤。

代码功能：实现两个.c文件，一个向另一个里面发送，另一个接收，实现服务器和客户端之间的通信。

#include<stdio.h>
#include<string.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<arpa/inet.h>
#include <errno.h>
#include <stdlib.h>
#define PORTNUM 3333

int main()
{
    int sockfd;
    int ret;
    int sock_fd;
    int addlen = sizeof(struct sockaddr);

    struct sockaddr_in my_addr,your_addr;
    char buf[512];
    int recvbytes;

    //socketd
    if((sockfd = socket(AF_INET,SOCK_STREAM,0)) < 0)
    {
        printf("socket error\n");
    }
    //bind
    bzero(&my_addr,sizeof(struct sockaddr));
    my_addr.sin_family = AF_INET;
    my_addr.sin_port = htons(PORTNUM);
    my_addr.sin_addr.s_addr = inet_addr("192.168.1.211");
    
    if((ret = bind(sockfd,(struct sockaddr *)&my_addr,addlen))<0)
    {
        printf("bind error\n");
    }
    while(1)
    {
    //listen
    if(listen(sockfd,5) < 0)
    {
        printf("listen error\n");
    }
    //accept
    bzero(&your_addr,sizeof(struct sockaddr));
    if((sock_fd = accept(sockfd,(struct sockaddr *)&your_addr,&addlen)) < 0)
    {
        printf("accept error\n");
    }

    //resv
    recvbytes = recv(sock_fd,buf,512,0);
    if(recvbytes < 0){
    	perror("recv");
	exit(-1);
	}
    buf[recvbytes] = '\0';
    printf("buf is %s\n",buf);
}
    //close
    close(sockfd);
    close(sock_fd);
}

<pre name="code" class="html">#include<stdio.h>
#include<string.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<arpa/inet.h>

#define PORTNUM 3333

int main()
{
    int sockfd;
    int ret;
    int sock_fd;
    int addlen = sizeof(struct sockaddr);

    struct sockaddr_in my_addr,your_addr;
    char buf[512];
    int sendbytes;

    //socketd
    while(1)
    {
    if((sockfd = socket(AF_INET,SOCK_STREAM,0)) < 0)
    {
        printf("socket error\n");
    }
    //connect
    bzero(&my_addr,sizeof(struct sockaddr));
    my_addr.sin_family = AF_INET;
    my_addr.sin_port = htons(PORTNUM);
    my_addr.sin_addr.s_addr = inet_addr("192.168.1.211");
    
    if((ret = connect(sockfd,(struct sockaddr *)&my_addr,addlen))<0)
    {
        printf("connect error\n");
    }

    //accept
   // if((sock_fd = accept(sockfd,(struct sockaddr *)&your_addr,&addlen)) < 0)
   // {
   //     printf("accept error\n");
   // }
    //send
   // char *msg = "cangyi";
    printf("please input \n");
    scanf("%s",buf);
    sendbytes = send(sockfd,(void *)buf,512,0);
    //close
    
    close(sockfd);
    close(sock_fd);
    }

}