socket tcp server -clinet

#include <sys/types.h>#include <sys/socket.h>#include <stdio.h>#include <stdlib.h>#include <errno.h>#include <string.h>#include <unistd.h>#include <netinet/in.h>#define SERVPORT 3333#define BACKLOG 10#define MAX_CONNECTED_NO 10#define MAXDATASIZE 10int main(){struct sockaddr_in server_sockaddr,client_sockaddr;int sin_size,recvbytes;int sockfd,client_fd;char buf[MAXDATASIZE];if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1){perror("socket");exit(1);}printf("socket success!,sockfd=%d\n",sockfd);server_sockaddr.sin_family=AF_INET;server_sockaddr.sin_port=htons(SERVPORT);server_sockaddr.sin_addr.s_addr=INADDR_ANY;bzero(&(server_sockaddr.sin_zero),8);if(bind(sockfd,(struct sockaddr *)&server_sockaddr,sizeof(struct sockaddr))==-1){perror("bind");exit(1);}printf("bind success!\n");if(listen(sockfd,BACKLOG)==-1){perror("listen");exit(1);}printf("listening...\n");if((client_fd=accept(sockfd,(struct sockaddr *)&client_sockaddr,&sin_size))==-1){perror("accept");exit(1);}if((recvbytes=recv(client_fd,buf,MAXDATASIZE,0))==-1){perror("recv");exit(1);}printf("received a connection:%s\n",buf);close(sockfd);}

#include<sys/types.h>#include<sys/socket.h>#include<errno.h>#include<string.h>#include<netinet/in.h>#include<stdio.h>#include<stdlib.h>#include<netdb.h>#define SERVERPORT 3333#define MAXDATASIZE 100main(int argc,char *argv[]){int sockfd,sendbytes;char buf[MAXDATASIZE];struct hostent *host;struct sockaddr_in serv_addr;if(argc<2){fprintf(stderr,"please enter the server's hostname!\n");exit(1);}if((host=gethostbyname(argv[1]))==NULL){perror("socket");exit(1);}if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1){perror("socket");exit(1);}serv_addr.sin_family=AF_INET;serv_addr.sin_port=htons(SERVERPORT);serv_addr.sin_addr=*((struct in_addr *)host->h_addr);bzero(&(serv_addr.sin_zero),8);if(connect(sockfd,(struct sockaddr *)&serv_addr,sizeof(struct sockaddr))==-1){perror("connect");exit(1);}char a[100];gets(a);if((sendbytes=send(sockfd,a,sizeof(a),0))==-1){perror("send");exit(1);}close(sockfd);}