tcp

问题 I'm currently developing a Java WebSocket Client Application and I have to make sure that every message from the server is received by the client. Is it possible that I lose some messages (once they are sent from the server) due to a connection interruption? WebSocket is based on TCP so this shouldn't happen right? 回答1: It can happen. TCP guarantees the order of packets, but it does not mean that all packets sent from a server reach a client even when an unrecoverable trouble happens in an

问题 After sending data over a socket with Winsock, you're supposed to close the connection like this: closesocket(ConnectSocket); WSACleanup(); I'm writing an API that sends data over a socket. If I have to close the socket afterwards, I need to add a function to the API so that users can say when they're done getting data. Is it a problem if I don't close the socket, for convenience? 回答1: One way or another, if you don't close a socket, your program will leak a file descriptor. Programs can

问题 After sending data over a socket with Winsock, you're supposed to close the connection like this: closesocket(ConnectSocket); WSACleanup(); I'm writing an API that sends data over a socket. If I have to close the socket afterwards, I need to add a function to the API so that users can say when they're done getting data. Is it a problem if I don't close the socket, for convenience? 回答1: One way or another, if you don't close a socket, your program will leak a file descriptor. Programs can

问题 I'm creating application based on ToyVPN to capture tcp/udp packets. After i get outgoing packets in my apllication i would like to forward them to original destination. I have managed to get destination ip and port from headers but i have no idea how to communicate with remote server and then write response back to the source. I think this is possible because there is this app. Here is my first first attempt: private void runVpnConnection() throws Exception { configure(); FileInputStream in

问题 I'm creating application based on ToyVPN to capture tcp/udp packets. After i get outgoing packets in my apllication i would like to forward them to original destination. I have managed to get destination ip and port from headers but i have no idea how to communicate with remote server and then write response back to the source. I think this is possible because there is this app. Here is my first first attempt: private void runVpnConnection() throws Exception { configure(); FileInputStream in

问题 I'm trying to create a server in Spring that's listening on a TCP port and accepts connections. I know how to route incoming requests to my service, and it can respond to those. However I would like to send messages to certain clients without any request received. For example, sometimes I have to inform a client about that it has got a message. To do this, I think I need a way to identify the clients, e.g. by letting them log in. Is there a way to have a "session" object for each active

问题 This works target.sin_addr.s_addr = inet_addr("127.0.0.1"); but I want to put the IP from a website URL I have tried const char host[] = "http://www.google.com/"; struct hostent *host_ip; host_ip = gethostbyaddr(host, strlen(host), 0); I of corse did WSAStartup before I used gethostbyaddr(); I've tried this target.sin_addr.s_addr = inet_addr(host_ip); I've tried a few simmilar ones too but it isn't working. Could someone show me how to do this correctly. Thank you! EDIT: When I do host_ip =

问题 i am using tcp socket for forwarding data (as class with type of request, and data) between server and client. When i send 6 object of order from client, the server get only 5 object of order, 1 is lost, but tcp is reliable protocol... (sometimes the server get 6 but usually get 5) Here's the client code HEADERSIZE = 10 PORT = 3000 SIZE = 4096 HOST = '127.0.0.1' soc = None ing_map = None def connect_to_client(): s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect((HOST, PORT))

问题 I have a service which as it's coming up invokes the Start() method on a TcpListener instance. This listener is using a port that is not common and not known to be used by any other services. Very very rarely for a span of minute or so it experiences an odd error. For a minute the service (which on failure restarts immediately) back to back crashes on the following exception: SocketException at System.Net.Sockets.Socket.DoBind(System.Net.EndPoint, System.Net.SocketAddress) at System.Net

问题 I am developing an web application which supports TCP connection by Spring Integration. It has two functions. send messages to Server and receive reply from Server at a time just receive messages from Server (The application on server is not developed by Spring Integration.) In this case, TCP Adapters should be used and I need provide to collaborate TCP Outbound and Inbound Channel Adapters. But, my application has a few restrictions. this application has no database. messages' payload format