Search Results

Search found 1680 results on 68 pages for 'berkeley sockets'.

Page 16/68 | < Previous Page | 12 13 14 15 16 17 18 19 20 21 22 23  | Next Page >

  • Socket ping-pong performance

    - by Kamil_H
    I have written two simple programs (tried it in C++ and C#). This is pseudo code: -------- Client --------------- for(int i = 0; i < 200.000; i++) { socket_send("ping") socket_receive(buff) } --------- Server ------------- while(1) { socket_receive(buff) socket_send("pong") } I tried it on Windows. Execution time of client is about 45 seconds. Can somebody explain me why this takes so long? I understand that if there were real network connection between client and server the time of one 'ping-pong' would be: generate_ping + send_via_network + generate_pong + send_via_network but here everything is done in 'local' mode. Is there any way to make this inter process ping-pong faster using network sockets (I'm not asking about shared memory for example :) )

    Read the article

  • Can I close and reopen a socket?

    - by Roman
    I learned an example of usage of sockets. In this example a client sends a request to a server to open a socket and then the server (listening to a specific port) opens a socket and everything is fine, socket is "opened" from both sides (client and server). But it is still not clear to me how flexible is this stuff. For example, is it possible for the client to close an opened (from both ends) socket and to reopen it again (under condition that the server keeps the socket opened). Is it possible for the server to "know" that a socket was closed on the client side? Is it possible for the client to know that a socket was closed on the server side?

    Read the article

  • Communication between java server and matlab client

    - by user272587
    I'd like to establish a server(Java)/client (Matlab) communication using socket. They can send messages to each other. An example shows how to do this in Java server and Java client, http://java.sun.com/docs/books/tutorial/networking/sockets/clientServer.html. When I try to rewrite the client part in Matlab, I only can get the first message that the Java server sends and display it in the Matlab command window. When I type a message in the Matlab command window, I can't pass it to the Java Server. Jave code: kkSocket = new Socket("localhost", 3434); Matlab equivalent: kkSocket = Socket('localhost', 3434); Java code for client: out = new PrintWriter(kkSocket.getOutputStream(), true); in = new BufferedReader(new InputStreamReader(kkSocket.getInputStream())); What would be a Matlab equivalent for this? Thanks in advance.

    Read the article

  • Socket.recv works but not gets or read?

    - by Earlz
    Hello I've been messing around with Sockets in Ruby some and came across some example code that I tried modifying and broke. I want to know why it's broken. Server: require "socket" dts = TCPServer.new('127.0.0.1', 20000) loop do Thread.start(dts.accept) do |s| print(s, " is accepted\n") s.write(Time.now) print(s, " is gone\n") s.close end end Client that works: require 'socket' streamSock = TCPSocket.new( "127.0.0.1", 20000 ) streamSock.print( "Hello\n" ) str = streamSock.recv( 100 ) print str streamSock.close Client that is broken require 'socket' streamSock = TCPSocket.new( "127.0.0.1", 20000 ) streamSock.print( "Hello\n" ) str=streamSock.read #this line modified print str streamSock.close I know that the streamSock.print is unnecessary (as well as the naming scheme being non-ruby) but I don't understand why read doesn't work while recv does, Why is this?

    Read the article

  • How to ensure that a Serialized object is completely read over a Socket ?

    - by Amitd
    Hi guys, I am trying to write a socket server and Client that communicate with each other via serialized Objects.eg:To Login, Client sends server a serialized Login object and then the server deserialises the object to read login details. Similarly for other types of request/response. I just wanted to be sure if Socket.receive() can read(untill) large serialized objects completely. I have tried this code but seems to fail when a large object is serialised and sent over the internet.(seems to work fine in LAN situations.) http://stackoverflow.com/questions/2134356/sending-large-serialized-objects-over-sockets-is-failing-only-when-trying-to-grow using(MemoryStream ms = new MemoryStream()) { int bytesRead; while((bytesRead = m_socClient.Receive(buffer)) > 0) { ms.Write(buffer, 0, bytesRead); } // access ms.ToArray() or ms.GetBuffer() as desired, or // set Position to 0 and read } Are there any other ways to ensure that the object gets completely read.

    Read the article

  • Custom SQL Server driver

    - by hoodoos
    I had a crazy thought about writing my own SQL Server driver to make it work something like non-blocking http client, so it won't be thread thirsty and could handle lots of db queries within one thread. I tried to look over google for some guidelines about implementing SQL Server client protocol, but found none really, where do those guys get information about it when they write own implementations for PHP or python? I need a really low level to be documented so I can implement all phases of working with a connection through sockets. And would be really nice to have a an example in c# language. :)

    Read the article

  • Auto enter pass phrase in case of Python ssl Client/Server

    - by rauch
    I need to create Client/Server application to send files from clients to Server. I use simple ssl sockets for that and authenticate with certificates. ms = socket.socket(socket.AF_INET, socket.SOCK_STREAM) ssl_sock = ssl.wrap_socket(ms, keyfile=".../newCA/my_client.key", certfile=".../newCA/my_client.crt", server_side=0, cert_reqs=ssl.CERT_REQUIRED, ca_certs=".../newCA/CA/my-ca.crt" ) ssl_sock.connect((HOST, MPORT)) And Server side: msock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) self.ssl_sock = ssl.wrap_socket(msock, keyfile=".../newCA/my_server.key", certfile=".../newCA/my_server.crt", server_side=1, cert_reqs=ssl.CERT_REQUIRED, ca_certs=".../newCA/CA/my-ca.crt" ) self.ssl_sock.bind(('', self.PORT)) self.ssl_sock.listen(self.QUEUE_MAX) The problem is the following: when client tries to connect to Server, it requires Enter the pass phrase for private key for Both: for Server-side and Client-side. In Java we need to set System Property: javax.net.ssl.keyStorePassword="" and it has to be used automatically, But how is it been used in Python? I can't enter pass phrase all time the client connects.

    Read the article

  • How to create an adhoc network between laptops in java?

    - by Muaz
    Hello, I want to create an adhoc between labtops were they will communicate using wireless communication. I will use java for this but still I do not know how to start.. I think I'll have to use sockets for the connections right? How will a laptop notice other laptops in its local network or the other way around? Do i need a server to handle the communication between laptops? Another thing, how to broadcast a message from one laptop to other laptops in the network? Please reply as soon as you can. Any help will be appreciated. Thanks in advance.

    Read the article

  • How to test for secure SMTP mail service on a mail server

    - by Vinay S Shenoy
    I'm working on a project to auto-configure a user's email server settings in Java. I am extracting the mail server from his email address and looking up the MX records of that mail server using the DirContext class with com.sun.jndi.dns.DnsContextFactory. Then I'm opening a Socket to each server and testing them using a HELO command and checking the responses. My problem is that this works only when I test it with the unsecure SMTP port 25. How can I use it with the secure port 465? I tried using Secure Sockets by using SSLSocketFactory sslsocketfactory = (SSLSocketFactory)SSLSocketFactory.getDefault(); SSLSocket socket = (SSLSocket)sslsocketfactory.createSocket(mailserver, STANDARD_SMTP_PORT); But all connections get a timeout exception as follows alt1.gmail-smtp-in.l.google.com. java.net.ConnectException: Operation timed out Please help.

    Read the article

  • Struct sockaddr, sin_family is not a member

    - by leon22
    According to this article from msdn ( http://msdn.microsoft.com/en-us/library/windows/desktop/ms740496(v=vs.85).aspx) the struct varies depending on which protocol is selected! Now I want to use this code from http://www.intelliproject.net/articles/showArticle/index/check_tcp_udp_port to check if a port is open or not! Now I have the struct sockaddr as follows: struct sockaddr { ushort sa_family; char sa_data[14]; }; but need this strcuture: struct sockaddr { short sin_family; u_short sin_port; struct in_addr sin_addr; char sin_zero[8]; }; Which changes are necessary? (Ws2_32.lib is linked and following includes #define WIN32_LEAN_AND_MEAN // sockets #include "windows.h" #include <winsock2.h> #include <ws2tcpip.h> Thx

    Read the article

  • How to receive HTTP messages using Socket

    - by Poma
    I'm using Socket class for my web client. I can't use HttpWebRequest since it doesn't support socks proxies. So I have to parse headers and handle chunked encoding by myself. The most difficult thing is to determine length of content so I have to read it byte-by-byte. First I have to use ReadByte() to find last header ("\r\n\r\n" combination), then read chunk's size etc. But this approach has very poor performance. Can you suggest better solution? Maybe some open source examples or libraries that handle http request through sockets (not very big and complicated though, I'm a noob)

    Read the article

  • Is a Service Bus a good option to communicate with multiple external servers?

    - by PFreitas
    We are developing an application that communicates, via web services or TCP/IP sockets, with multiple servers (up to 50 different external companies). Basically, the exchanged messages are the same (XML), but depending on the inputs of our application we should call 1 or more external servers. The benefits we would expect of introducing a Service Bus in the architecture would be: 1- Remove the need to manage all point-to-point configurations (all the 50 endpoints); 2- Simplify the communication layer of our application by having only one server to talk to; Is a Service Bus a good architectural option for this scenario? What is the best (simplest) Service Bus for this kind of communication? I read a few MSDN articles on Azure Service Bus Relay, but it didn’t seem to fit our needs. Am I wrong? Thanks for your help.

    Read the article

  • Creating TCP network errors for unit testing

    - by Robert S. Barnes
    I'd like to create various network errors during testing. I'm using the Berkely sockets API directly in C++ on Linux. I'm running a mock server in another thread from within Boost.Test which listens on localhost. For instance, I'd like to create a timeout during connect. So far I've tried not calling accept in my mock server and setting the backlog to 1, then making multiple connections, but all seem to successfully connect. I would think that if there wasn't room in the backlog queue I would at least get a connection refused error if not a timeout. I'd like to do this all programatically if possible, but I'd consider using something external like IPchains to intentionally drop certain packets to certain ports during testing, but I'd need to automate creating and removing rules so I could do it from within my Boost.Test unit tests. I suppose I could mock the various system calls involved, but I'd rather go through a real TCP stack if possible. Ideas?

    Read the article

  • I have a ConnectException that isn't being caught for some reason

    - by aakbari1024
    I'm working on an Android application that uses sockets. I have a function called initializeStreams() which opens the socket and attempts a connection. This function throws a ConnectException if the connection could not be established. But for some reason, in the code that calls initializeStreams(), which has a catch block for ConnectException, the log prints out its own stack trace for the exception instead of going to the catch block. The catch block is never reached at all, even though the exact exception is being thrown. Here's the code: The try block: try { initializeStreams(); /* drivesList = new ArrayList<String>(); drivesList = enumerateDrives();*/ } catch (ConnectException e) { //Log.i(TAG, "caught connect exception"); /*loadingProgress.dismiss(); retryConnection();*/ } initializeStreams(): public void initializeStreams() throws ConnectException { try { Log.i(TAG, "Attempting to connect"); requestSocket = new Socket(SERVER_ADDR, PORT); /* other code */ } catch (IOException e) { e.printStackTrace(); } I can't figure this out, so any help would be much appreciated. }

    Read the article

  • Network programming on java

    - by maks
    I have written a simple network program on java using sockets. Program has a client and a server. When user types a word on client side, server simply return this word to client. On server side I use Serversocket and bind it to port 4444. Why does not firewall block this connection on my server PC? I ask this question because earlier I wrote this program using corba technology, and firewall on my server PC was blocking the connection to this port; when I disabled the firewall the program worked fine.

    Read the article

  • Sending a large file over network continuously

    - by David Parunakian
    Hello, We need to write software that would continuously (i.e. new data is sent as it becomes available) send very large files (several Tb) to several destinations simultaneously. Some destinations have a dedicated fiber connection to the source, while some do not. Several questions arise: We plan to use TCP sockets for this task. What failover procedure would you recommend in order to handle network outages and dropped connections? What should happen upon upload completion: should the server close the socket? If so, then is it a good design decision to have another daemon provide file checksums on another port? Could you recommend a method to handle corrupted files, aside from downloading them again? Perhaps I could break them into 10Mb chunks and calculate checksums for each chunk separately? Thanks.

    Read the article

  • How to read from port#### on home IP 127.0.0.1 [SOLVED]

    - by Ree
    I have a program that sends data to the home IP to the port####. I want to access this and make it readable data. Maybe in C#? I haven't tried doing this before and I have only a vague idea of doing sockets. Any ideas as to how I can manage this? Thanks - Ree EDIT The program I'm trying access is a UDP. Therefore it's a UDP port reader I need to incorporate on another program. "####" < is just any random number. SOLUTION: http://msdn.microsoft.com/en-us/library/tst0kwb1.aspx

    Read the article

  • Stocket server crashing with unhandled exception

    - by Rob
    We have a c# (3.5 framework) socket server which is a console app, after about 3000 connections (or less, it's quite random), we get an unhandled exception which crashes the app completely. We're really struggling to find out what's happening and where, the only info we get is below, can anyone shed any light? It should be noted that EVERYTHING is wrapped up in try catch{} Description: Stopped working Problem signature: Problem Event Name: CLR20r3 Problem Signature 01: qrushrserver.exe Problem Signature 02: 1.0.0.0 Problem Signature 03: 4bf56a0c Problem Signature 04: System Problem Signature 05: 2.0.0.0 Problem Signature 06: 49cc5ec9 Problem Signature 07: 2c0b Problem Signature 08: 40 Problem Signature 09: System.Net.Sockets.Socket OS Version: 6.0.6002.2.2.0.1296.17 Locale ID: 2057 Faulting application app_name.exe, version 1.0.0.0, time stamp 0x4bf56a0c, faulting module mscorwks.dll, version 2.0.50727.4200, time stamp 0x4a9ee32d, exception code 0xc0000005, fault offset 0x00000000001c89ca, process id 0x%9, application start time 0x%10. .NET Runtime version 2.0.50727.4200 - Fatal Execution Engine Error (000007FEF8E4664E) (80131506)

    Read the article

  • How to empty a socket in python?

    - by luc
    I need to empty the data on a socket (making sure that there is nothing to receive). Unfortunately, there is no function for this in the python socket module. I've implemented something this way: def empty_socket(sock): """remove the data present on the socket""" input = [sock] while 1: inputready, o, e = select.select(input,[],[], 0.0) if len(inputready)==0: break for s in inputready: s.recv(1) What do you think? Is there a better way to do that? Update: I don't want to change the socket timeout. What's why i prefer a select to a read. Update: The original question was using the 'flush' term. It seems that 'empty' is a better term. Update - 2010-02-27 : I've noticed a bug after when the pair has closed. The inputready is always filled with the sockets. I fixed that by adding a maximum number of loops. Is there a better fix?

    Read the article

  • Send data over telnet without pressing enter

    - by Matt
    I've recently started messing around with Java sockets and telnet... I want the user to be able to connect to the server, just type a letter and have it sent to the server, without pressing enter to send it. I'm sure there's no way for the server to set this up, but maybe telnet has a parameter or something which could allow this? Maybe if I got the user to type stty cbreak or stty raw before running telnet, this would work? (UNIX only, I know!) If I can get telnet to do this then it saves me having to write a special client just for this feature...

    Read the article

  • Find original owning process of a Linux socket

    - by Rob H
    In Linux and other UNIX-like operating systems, it is possible for two (or more) processes to share an Internet socket. Assuming there is no parent-child relationship between the processes, is there any way to tell what process originally created a socket? Clarification: I need to determine this from "outside" the processes using the /proc filesystem or similar. I can't modify the code of the processes. I can already tell what processes are sharing sockets by reading /proc/<pid>/fd, but that doesn't tell me what process originally created them.

    Read the article

  • Socket c# not listen on port over internet?

    - by Nguy?n Van Th?ng
    Code server I have server listen on port 1450: //Using UDP sockets clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp); EndPoint ourEP = new IPEndPoint(IPAddress.Any, 1450); //Listen asynchronously on port 1450 for coming messages (Invite, Bye, etc). clientSocket.Bind(ourEP); //Receive data from any IP. EndPoint remoteEP = (EndPoint)(new IPEndPoint(IPAddress.Any, 0)); byteData = new byte[1024]; //Receive data asynchornously. clientSocket.BeginReceiveFrom(byteData, 0, byteData.Length, SocketFlags.None, ref remoteEP, new AsyncCallback(OnReceive), null); but code on not open port 1450 and client connect: otherPartyIP = new IPEndPoint(IPAddress.Parse(txtCallToIP.Text), 1450); otherPartyEP = (EndPoint)otherPartyIP; When i run code client and server in lan network it's ok. but run over network i check port 1450 in lan not open. tell me how open port 1450 in code server? thanks

    Read the article

  • Forking with a listening socket

    - by viraptor
    I'd like to make sure about the correctness of the way I try to use accept() on a socket. I know that in Linux it's safe to listen() on a socket, fork() N children and then recv() the packets in all of them without any synchronisation from the user side (the packets get more or less load-balanced between the children). But that's UDP. Does the same property hold for TCP and listen(), fork(), accept()? Can I just assume that it's ok to accept on a shared socket created by the parent, even when other children do the same? Is POSIX, BSD sockets or any other standard defining it somewhere?

    Read the article

  • conditional beginReceive

    - by sbenderli
    I am writing a client program that uses Sockets. I would like the client to receive asyncronously UNLESS it is expecting a response, in which case I would like to receive syncronously. My current problem is that because I have to make a call to socket.BeginReceive which waits until there's data on the buffer, the async call always happens prior to the sync call.. How could I temporarily stop BeginReceive from executing? Is there a way to call EndReceive and then once I am done receiving syncronously, I can continue to receive asnycronously?

    Read the article

  • How can I limit the number of open AF_INET sockets?

    - by Stefano Palazzo
    Is there a way to limit the number of concurretly open AF_INET sockets (only)? If so, how do I do it, and how will the networking behave if I'm above the limit? For background: My cheap commodity router is a bit eager to detect 'syn flooding'. When it does, it crashes (and doesn't automatically restart itself). I'm thinking limiting concurrent connections to around 1000 should keep it from bickering.

    Read the article

< Previous Page | 12 13 14 15 16 17 18 19 20 21 22 23  | Next Page >