LINUX网络编程：程序可实现客户端和服务器端之间的对话(6月8号上传)

LINUX 下的 C 语言编程
简单的服务器端和客户端程序 任 ZR
程序可实现客户端和服务器端之间的对话。由于是靠终端运行，终端支持中文字符，所 以可以实现中文对话，但是由于 send 和 cv 命令的阻塞作用，因此这个只能做到简单的一 问一答的对话，不能像 QQ 那样的不需要顺序限制的对话。
服务器端： #include <stdio.h> #include<stdlib.h> #include<errno.h> #include <strings.h> /* for bzero() */ #include <unistd.h> /* for close() */ #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #define PORT 1234 /* Port that ill be opened */ #define BACKLOG 1 /* Number of allowed connetctions */ #define MAXDATASIZE 1000 void process_cli(int connectfd,struct sockaddr_in client); main() { int sockfd,new_fd; /* socket descriptors */ pid_t pid; struct sockaddr_in my_addr; /* server's address information */ struct sockaddr_in their_addr; /* client's address information */ int sin_size; /* Create TCP socket */ if ((sockfd = socket(AF_INET, SOCK_STREAM, 0))== -1){ /*handle exception */ perror("Creating socket failed."); exit(1); }/*set socket can be reused */ int opt = SO_REUSEADDR; setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)); bzero(&my_addr,sizeof(my_addr)); /* fill server with 0s */ my_addr.sin_family=AF_INET; my_addr.sin_port=htons(PORT); my_addr.sin_addr.s_addr = htonl (INADDR_ANY); if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr))== -1) { /* handle exception */ perror("Bind error."); exit(1); }
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LINUX 下的 C 语言编程
简单的服务器端和客户端程序 任 ZR
if(listen(sockfd,BACKLOG) == -1){ /*calls listen() */ perror("listen() error\n"); exit(1); } sin_size=sizeof(struct sockaddr_in); while(1) { /* accept connection */ if((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size))==-1){/* calls accept() */ perror("accept() error\n"); exit(1); } /* Creact child process to service client */ if ((pid=fork()>0)){ /* parent process */ close(new_fd); continue; } else if (pid==0){ /* child process */ close(sockfd); process_cli(new_fd,their_addr); exit(0); } else{ printf("fork error\n"); exit(0); } } close(sockfd); /* close listenfd */ } void process_cli(int connectfd,struct sockaddr_in client) { int num; FILE *fp=stdin; char recvbuf[MAXDATASIZE], sendbuf[MAXDATASIZE], cli_name[MAXDATASIZE];/*prints client's IP */ printf("You got a conneciton from %s\n",inet_ntoa(client.sin_addr)); /* Get client's name from client */ num=recv(connectfd, cli_name, MAXDATASIZE,0); if(num==0){ close(connectfd); printf("Client disconnected.\n");
客户端： #include <stdio.h> #include <unistd.h> #include <strings.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <netdb.h> #define PORT 1234 /* Open Port on Remote Host */ #define MAXDATASIZE 100 /* Max number of bytes of data */ void process(FILE *fp, int sockfd); char* getMessage(char* sendline,int len, FILE* fp); int main(int argc, char *argv[]) { int fd; /* files descriptors */ struct hostent *he; struct sockaddr_in server; /* server's address information */ if (argc !=2){ printf("Usage: %s<IPADDRESS>\n",argv[0]); exit(1); } if ((he=gethostbyname(argv[1]))==NULL){ printf("gethostbyname()error\n"); exit(1); } if((fd=socket(AF_INET, SOCK_STREAM, 0))==-1){ printf("socket() error\n"); exit(1); }
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LINUX 下的 C 语言编程
简单的服务器端和客户端程序 任 ZR
bzero(&server,sizeof(server)); server.sin_family = AF_INET; server.sin_port = htons(PORT); server.sin_addr=*((struct in_addr*)he->h_addr); if(connect(fd,(struct sockaddr *)&server, sizeof(struct sockaddr))==-1){ printf("connect() error\n"); exit(1); } process(stdin,fd); close (fd); } void process(FILE *fp, int sockfd) { char sendline[MAXDATASIZE], recvline[MAXDATASIZE]; int numbytes; printf("Connected to server.\n"); /* send name to server */ printf("Input name :"); if( fgets(sendline, MAXDATASIZE, fp)== NULL){ printf("\nEXIT.\n"); return; } send(sockfd, sendline, strlen(sendline), 0); /* send messsage to server */ while (getMessage(sendline, MAXDATASIZE, fp)!=NULL ){ send(sockfd,sendline,strlen(sendline),0); if ((numbytes = recv(sockfd, recvline, MAXDATASIZE, 0))==0){ printf("Server terminated.\n"); return; } recvline[numbytes]='\0'; printf("Server Message: %s\n",recvline); } printf("\nExit.\n"); } char* getMessage(char* sendline,int len,FILE* fp) { printf("Input string to server:"); return(fgets(sendline, MAXDATASIZE, fp)); }