From the java api documentation for Socket: public void close() throws IOException Closes this socket. Any thread currently blocked in an I/O operation upon this socket will throw a SocketException. Once a socket has been closed, it is not available for further networking use (i.e. can’t be reconnected or rebound). A new socket needs to … Read more
This depends in part on your operating system. There is however no limit on a specific port. There is a limit on the number of concurrent connections however, typically limited by the number of file descriptors the kernel supports (eg 2048). The thing to remember is that a TCP connection is unique and a connection … Read more
I am currently looking into the same questions. For me the possibility of adding Windows clients later makes the situation more complicated; in your case the answer seems to be simpler. About the options you have considered: Control files: While it is possible to communicate via control files, you have to keep in mind that … Read more
Yea, like Morrison said above, you probably need to put this permission to your manifest file. <uses-permission android:name=”android.permission.INTERNET” />
Assume your socket is named s… you need to set socket.SO_REUSEADDR on the server’s socket before binding to an interface… this will allow you to immediately restart a TCP server… s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) s.bind((ADDR, PORT))
“Unexpected end of file” implies that the remote server accepted and closed the connection without sending a response. It’s possible that the remote system is too busy to handle the request, or that there’s a network bug that randomly drops connections. It’s also possible there is a bug in the server: something in the request … Read more
I had a similar problem and had to convert the URL from string to Uri object using: Uri myUri = new Uri(URLInStringFormat, UriKind.Absolute); (URLInStringFormat is your URL) Try to connect using the Uri instead of the string as: WebClient client = new WebClient(); client.OpenRead(myUri);
CLOSE_WAIT means your program is still running, and hasn’t closed the socket (and the kernel is waiting for it to do so). Add -p to netstat to get the pid, and then kill it more forcefully (with SIGKILL if needed). That should get rid of your CLOSE_WAIT sockets. You can also use ps to find … Read more
TCP is a streaming protocol with no concept of message boundaries, so if you print msgp you will see it received more than you expected, probably folder name, number of files, and part of the binary file data. Since that data isn’t UTF-8 encoded, you get a UnicodeDecodeError. You have to define a protocol and … Read more
Beej’s famous network programming guide gives a nice explanation: In some documentation, you’ll see mention of a mystical “PF_INET”. This is a weird etherial beast that is rarely seen in nature, but I might as well clarify it a bit here. Once a long time ago, it was thought that maybe a address family (what … Read more