linux下socket通訊，server和client簡單例子
阿新 • • 發佈：2019-02-08
<span style="font-family: Arial, Helvetica, sans-serif;">server.c</span>==================================================================== #include <netinet/in.h> // for sockaddr_in #include <sys/types.h> // for socket #include <sys/socket.h> // for socket #include <stdio.h> // for printf #include <stdlib.h> // for exit #include <string.h> // for bzero /* #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> */ #define HELLO_WORLD_SERVER_PORT 6666 #define LENGTH_OF_LISTEN_QUEUE 20 #define BUFFER_SIZE 1024 #define FILE_NAME_MAX_SIZE 512 int main(int argc, char **argv) { //設定一個socket地址結構server_addr,代表伺服器internet地址, 埠 struct sockaddr_in server_addr; bzero(&server_addr,sizeof(server_addr)); //把一段記憶體區的內容全部設定為0 server_addr.sin_family = AF_INET; server_addr.sin_addr.s_addr = htons(INADDR_ANY); server_addr.sin_port = htons(HELLO_WORLD_SERVER_PORT); //建立用於internet的流協議(TCP)socket,用server_socket代表伺服器socket int server_socket = socket(PF_INET,SOCK_STREAM,0); if( server_socket < 0) { printf("Create Socket Failed!"); exit(1); } { int opt =1; setsockopt(server_socket,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt)); } //把socket和socket地址結構聯絡起來 if( bind(server_socket,(struct sockaddr*)&server_addr,sizeof(server_addr))) { printf("Server Bind Port : %d Failed!", HELLO_WORLD_SERVER_PORT); exit(1); } //server_socket用於監聽 if ( listen(server_socket, LENGTH_OF_LISTEN_QUEUE) ) { printf("Server Listen Failed!"); exit(1); } while (1) //伺服器端要一直執行 { //定義客戶端的socket地址結構client_addr struct sockaddr_in client_addr; socklen_t length = sizeof(client_addr); //接受一個到server_socket代表的socket的一個連線 //如果沒有連線請求,就等待到有連線請求--這是accept函式的特性 //accept函式返回一個新的socket,這個socket(new_server_socket)用於同連線到的客戶的通訊 //new_server_socket代表了伺服器和客戶端之間的一個通訊通道 //accept函式把連線到的客戶端資訊填寫到客戶端的socket地址結構client_addr中 int new_server_socket = accept(server_socket,(struct sockaddr*)&client_addr,&length); if ( new_server_socket < 0) { printf("Server Accept Failed!\n"); break; } char buffer[BUFFER_SIZE]; bzero(buffer, BUFFER_SIZE); length = recv(new_server_socket,buffer,BUFFER_SIZE,0); if (length < 0) { printf("Server Recieve Data Failed!\n"); break; } char file_name[FILE_NAME_MAX_SIZE+1]; bzero(file_name, FILE_NAME_MAX_SIZE+1); strncpy(file_name, buffer, strlen(buffer)>FILE_NAME_MAX_SIZE?FILE_NAME_MAX_SIZE:strlen(buffer)); // int fp = open(file_name, O_RDONLY); // if( fp < 0 ) printf("%s\n",file_name); FILE * fp = fopen(file_name,"r"); if(NULL == fp ) { printf("File:\t%s Not Found\n", file_name); } else { bzero(buffer, BUFFER_SIZE); int file_block_length = 0; // while( (file_block_length = read(fp,buffer,BUFFER_SIZE))>0) while( (file_block_length = fread(buffer,sizeof(char),BUFFER_SIZE,fp))>0) { printf("file_block_length = %d\n",file_block_length); //傳送buffer中的字串到new_server_socket,實際是給客戶端 if(send(new_server_socket,buffer,file_block_length,0)<0) { printf("Send File:\t%s Failed\n", file_name); break; } bzero(buffer, BUFFER_SIZE); } // close(fp); fclose(fp); printf("File:\t%s Transfer Finished\n",file_name); } //關閉與客戶端的連線 close(new_server_socket); } //關閉監聽用的socket close(server_socket); return 0; }
client程式碼
client.c #include <netinet/in.h> // for sockaddr_in #include <sys/types.h> // for socket #include <sys/socket.h> // for socket #include <stdio.h> // for printf #include <stdlib.h> // for exit #include <string.h> // for bzero /* #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> */ #define HELLO_WORLD_SERVER_PORT 6666 #define BUFFER_SIZE 1024 #define FILE_NAME_MAX_SIZE 512 int main(int argc, char **argv) { if (argc != 2) { printf("Usage: ./%s ServerIPAddress\n",argv[0]); exit(1); } //設定一個socket地址結構client_addr,代表客戶機internet地址, 埠 struct sockaddr_in client_addr; bzero(&client_addr,sizeof(client_addr)); //把一段記憶體區的內容全部設定為0 client_addr.sin_family = AF_INET; //internet協議族 client_addr.sin_addr.s_addr = htons(INADDR_ANY);//INADDR_ANY表示自動獲取本機地址 client_addr.sin_port = htons(0); //0表示讓系統自動分配一個空閒埠 //建立用於internet的流協議(TCP)socket,用client_socket代表客戶機socket int client_socket = socket(AF_INET,SOCK_STREAM,0); if( client_socket < 0) { printf("Create Socket Failed!\n"); exit(1); } //把客戶機的socket和客戶機的socket地址結構聯絡起來 if( bind(client_socket,(struct sockaddr*)&client_addr,sizeof(client_addr))) { printf("Client Bind Port Failed!\n"); exit(1); } //設定一個socket地址結構server_addr,代表伺服器的internet地址, 埠 struct sockaddr_in server_addr; bzero(&server_addr,sizeof(server_addr)); server_addr.sin_family = AF_INET; if(inet_aton(argv[1],&server_addr.sin_addr) == 0) //伺服器的IP地址來自程式的引數 { printf("Server IP Address Error!\n"); exit(1); } server_addr.sin_port = htons(HELLO_WORLD_SERVER_PORT); socklen_t server_addr_length = sizeof(server_addr); //向伺服器發起連線,連線成功後client_socket代表了客戶機和伺服器的一個socket連線 if(connect(client_socket,(struct sockaddr*)&server_addr, server_addr_length) < 0) { printf("Can Not Connect To %s!\n",argv[1]); exit(1); } char file_name[FILE_NAME_MAX_SIZE+1]; bzero(file_name, FILE_NAME_MAX_SIZE+1); printf("Please Input File Name On Server:\t"); scanf("%s", file_name); char buffer[BUFFER_SIZE]; bzero(buffer,BUFFER_SIZE); strncpy(buffer, file_name, strlen(file_name)>BUFFER_SIZE?BUFFER_SIZE:strlen(file_name)); //向伺服器傳送buffer中的資料 send(client_socket,buffer,BUFFER_SIZE,0); // int fp = open(file_name, O_WRONLY|O_CREAT); // if( fp < 0 ) FILE * fp = fopen(file_name,"w"); if(NULL == fp ) { printf("File:\t%s Can Not Open To Write\n", file_name); exit(1); } //從伺服器接收資料到buffer中 bzero(buffer,BUFFER_SIZE); int length = 0; while( length = recv(client_socket,buffer,BUFFER_SIZE,0)) { if(length < 0) { printf("Recieve Data From Server %s Failed!\n", argv[1]); break; } // int write_length = write(fp, buffer,length); int write_length = fwrite(buffer,sizeof(char),length,fp); if (write_length<length) { printf("File:\t%s Write Failed\n", file_name); break; } bzero(buffer,BUFFER_SIZE); } printf("Recieve File:\t %s From Server[%s] Finished\n",file_name, argv[1]); close(fp); //關閉socket close(client_socket); return 0; }