socket编程的基础函数使用请自查询，本文只给出在linux gcc可编译运行的socket通信的服务器程序与客户端程序。
代码如下：server端
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h> //signal
#include <sys/socket.h> //socket
#include <netinet/in.h> //sockaddr_in
#include <arpa/inet.h>
#include <string.h> //memset
const int BUFF_SIZE=10;
void process(int client_fd,int cmd)
{
switch(cmd)
{
case 0:
printf("rec cmd 0");break;
case 1:
default:
printf("default %d\n",cmd);break;
}
send(client_fd,"OK",BUFF_SIZE,0);
}
int main(void) {
int server_fd,client_fd; //socket fd
struct sockaddr_in my_addr; //服务器网络地址结构体
struct sockaddr_in remote_addr; //客户端网络地址结构体
int cmd;
char str[10];
pid_t pid;
unsigned int len;
//1.init
memset(&my_addr,0,sizeof(my_addr));//数据初始化--清零
my_addr.sin_family=AF_INET; //设置为IP通信
my_addr.sin_addr.s_addr=INADDR_ANY;//服务器IP地址--允许连接到所有本地地址上
my_addr.sin_port=htons(8000); //服务器端口号
//2.socket
if( (server_fd = socket(AF_INET,SOCK_STREAM,0)) < 0)//create socket;
{
perror("socket create failed");
exit(-1);
}
//3.bind
if (bind(server_fd,(struct sockaddr *)&my_addr,sizeof(struct sockaddr))<0)
{
perror("bind failed");
return 1;
}
//4.listen
listen(server_fd,5);
puts("Now server begin listening ,the listen queue len is5");
signal(SIGCLD,SIG_IGN); //ignore teh detail of the child process exit
int client_len = sizeof(remote_addr);
while(1){
//5.accept
if((client_fd=accept(server_fd,(struct sockaddr *)&remote_addr,&client_len))<0)
{
perror("accept");
return 1;
}
if( (pid = fork())== 0) //child
{
// client_fd= accept(server_fd,(struct sockaddr*)&remote_addr,&client_len);
// puts("a client connected");
//6.receive
printf("working for %s\n",inet_ntoa(remote_addr.sin_addr));
len = send(client_fd,"welcome!",BUFF_SIZE,0);
puts("send welcome!");
len = recv(client_fd,&cmd,sizeof(cmd),0);
process(client_fd,cmd);
close(client_fd);
exit(0);
}
if(pid) //parent
{
puts("In parent process");
close(client_fd);
// puts("parent process over");
sleep(1);
}
}
close(server_fd);
return EXIT_SUCCESS;
}
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h> //signal
#include <sys/socket.h> //socket
#include <netinet/in.h> //sockaddr_in
#include <arpa/inet.h>
#include <string.h> //memset
const int BUFF_SIZE=10;
int main(void) {
int client_sockfd;
int len,cmd;
struct sockaddr_in remote_addr; //服务器端网络地址结构体
char buf[BUFF_SIZE]; //数据传送的缓冲区
memset(&remote_addr,0,sizeof(remote_addr)); //数据初始化--清零
remote_addr.sin_family=AF_INET; //设置为IP通信
remote_addr.sin_addr.s_addr=inet_addr("127.0.0.1");//服务器IP地址
remote_addr.sin_port=htons(8000); //服务器端口号
if((client_sockfd=socket(PF_INET,SOCK_STREAM,0))<0)
{
perror("socket");
return 1;
}
if(connect(client_sockfd,(struct sockaddr *)&remote_addr,sizeof(struct sockaddr))<0)
{
perror("connect");
return 1;
}
printf("connected to server\n");
len=recv(client_sockfd,buf,BUFSIZ,0);//接收服务器端信息
buf[len]=‘/0‘;
printf("received %s\n",buf); //打印服务器端信息
puts("please input cmd");
scanf("%d",&cmd);
len=send(client_sockfd,&cmd,4,0);
len=recv(client_sockfd,buf,BUFF_SIZE,0);
buf[len]=‘/0‘;
printf("received %s\n",buf); //打印服务器端信息
close(client_sockfd);//关闭套接字
return 0;
}