一、简介
直接推荐此博文:
https://blog.csdn.net/weixin_44923289/article/details/106614967?utm_medium=distribute.pc_category.none-task-blog-hot-20.nonecase&depth_1-utm_source=distribute.pc_category.none-task-blog-hot-20.nonecase&request_id=
https://blog.csdn.net/daaikuaichuan/article/details/83475809
二、实战:
client代码:
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<errno.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#define MAXLINE 4096
int main(int argc, char** argv)
{
int sockfd, n,rec_len;
char recvline[4096], sendline[4096];
char buf[MAXLINE];
struct sockaddr_in servaddr;
if( argc != 2){
printf("usage: ./client <ipaddress>\n");
exit(0);
}
if( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0){
printf("create socket error: %s(errno: %d)\n", strerror(errno),errno);
exit(0);
}
memset(&servaddr, 0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(8000);
if( inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0){
printf("inet_pton error for %s\n",argv[1]);
exit(0);
}
if( connect(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr)) < 0){
printf("connect error: %s(errno: %d)\n",strerror(errno),errno);
exit(0);
}
printf("send msg to server: \n");
fgets(sendline, 4096, stdin);
if( send(sockfd, sendline, strlen(sendline), 0) < 0)
{
printf("send msg error: %s(errno: %d)\n", strerror(errno), errno);
exit(0);
}
if((rec_len = recv(sockfd, buf, MAXLINE,0)) == -1) {
perror("recv error");
exit(1);
}
buf[rec_len] = '\0';
printf("Received : %s ",buf);
close(sockfd);
exit(0);
}
server代码:
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<errno.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#define DEFAULT_PORT 8000
#define MAXLINE 4096
int main(int argc, char** argv)
{
int socket_fd, connect_fd;
struct sockaddr_in servaddr;
char buff[4096];
int n;
//初始化Socket
if( (socket_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1 ){
printf("create socket error: %s(errno: %d)\n",strerror(errno),errno);
exit(0);
}
//初始化
memset(&servaddr, 0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);//IP地址设置成INADDR_ANY,让系统自动获取本机的IP地址。
servaddr.sin_port = htons(DEFAULT_PORT);//设置的端口为DEFAULT_PORT
//将本地地址绑定到所创建的套接字上
if( bind(socket_fd, (struct sockaddr*)&servaddr, sizeof(servaddr)) == -1){
printf("bind socket error: %s(errno: %d)\n",strerror(errno),errno);
exit(0);
}
//开始监听是否有客户端连接
if( listen(socket_fd, 10) == -1){
printf("listen socket error: %s(errno: %d)\n",strerror(errno),errno);
exit(0);
}
printf("======waiting for client's request======\n");
while(1){
//阻塞直到有客户端连接,不然多浪费CPU资源。
if( (connect_fd = accept(socket_fd, (struct sockaddr*)NULL, NULL)) == -1){
printf("accept socket error: %s(errno: %d)",strerror(errno),errno);
continue;
}
//接受客户端传过来的数据
n = recv(connect_fd, buff, MAXLINE, 0);
//向客户端发送回应数据
if(!fork()){ /*紫禁城*/
if(send(connect_fd, "Hello,you are connected!\n", 26,0) == -1)
perror("send error");
close(connect_fd);
exit(0);
}
buff[n] = '\0';
printf("recv msg from client: %s\n", buff);
close(connect_fd);
}
close(socket_fd);
}