Linux socket编程-最简单的服务器和客户端程序

转载自：http://blog.csdn.net/yangliuy/article/details/7420770

复习了一下Linux socket编程，写了最简单的服务器和客户端程序，测试通过，其中服务器端程序采用循环忙等待，后面会改成多线程及线程池机制

服务器端程序

 #include <cstdlib>
 #include <iostream>
 #include <cstring>
 #include <cstdio>
 #include <cerrno>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <string>

 using namespace std;
 #define BACKLOG 10

 int main(int argc, char * argv[]){
     int connfd, sockfd;
     struct sockaddr_in servaddr;
     struct sockaddr_in tempaddr;
     struct sockaddr_in cliaddr;
     socklen_t clilen;
     char ip_str[INET_ADDRSTRLEN];
     int ret_val;

     socklen_t templen;
     sockfd = socket(AF_INET, SOCK_STREAM, 0);
     if(sockfd == -1){
         perror("socket");
         exit(1);
     }

     bzero(&servaddr, sizeof(servaddr));
     servaddr.sin_family = AF_INET;
     servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
     servaddr.sin_port = 0;

     ret_val = bind(sockfd,(struct sockaddr *)&servaddr, sizeof(servaddr));
     if(ret_val == -1){
         perror("bind");
         exit(1);
     }
     cout<< "the sockfd is "<< sockfd << endl;
     ret_val = listen(sockfd,BACKLOG);
     if(ret_val == -1){
         perror("listen");
         exit(1);
     }

     templen = sizeof(struct sockaddr);
     ret_val =  getsockname(sockfd, (struct sockaddr *)&tempaddr, &templen);
     if(ret_val == -1){
         perror("getsockname");
         exit(1);
     }

     cout<<"Server is listening on port "<< ntohs(tempaddr.sin_port)<<endl;
     for(;;){
         clilen = sizeof(cliaddr);
         connfd = accept(sockfd,(struct sockaddr *) &cliaddr,&clilen);
         if(connfd == -1){
             perror("accept");
             continue;
         }
         cout<< " Sever: client "<< inet_ntoa(cliaddr.sin_addr) << " connect"<<endl;
         close(connfd);
     }
     return 0;
 }

客户端程序

 #include <cstdlib>
 #include <cstdio>
 #include <cstring>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <unistd.h>

 #include <iostream>
 using namespace std;

 int main(int argc, char * argv[]){
     int sockfd;
     int conn_ret;
     struct sockaddr_in servaddr;
     if(argc != 3){
         cout<< "Usage : client <address> <port> " <<endl;
         return 0;
     }
     sockfd = socket(AF_INET,SOCK_STREAM,0);
     if (sockfd == -1){
         perror("sock");
         exit(1);
     }

     bzero(&servaddr,sizeof(servaddr));
     servaddr.sin_family = AF_INET;
         servaddr.sin_port = htons(atoi(argv[2]));
     inet_pton(AF_INET,argv[1],&servaddr.sin_addr);
     conn_ret = connect(sockfd, (struct sockaddr *)&servaddr,sizeof(servaddr));
     if(conn_ret == -1){
         perror("connect");
     }
     close(sockfd);
     return 0;
 }