Search Results

Search found 15377 results on 616 pages for 'socket programming'.

Page 259/616 | < Previous Page | 255 256 257 258 259 260 261 262 263 264 265 266  | Next Page >

• Software development, basics of design, conventions and scalability

  - by goce ribeski

  I need to improve my programming skills in order to achieve better scalability for the software I'm working on. Purpose is to learn the rules of adding new modules and features, so when it comes to maintaining existing ones there is some concept. So, I'm looking for a good book, tutorial or websites where I can continue to read about this. Currently, what I know and what I do is: to design relational database(3NF), make separate class for each table put that in MVC implement modular programming ...write code and hope for the best... I presume that next things I need to learn more deeply are: programming codex(naming, commenting, conventions...), organize functions building interfaces organizing custom made libraries, organizing API that I'm using, documenting, team work... ... At last what my job is, it does't need to affect your answer, PHP CodeIgniter developer.

  Read the article

• Cost of maintenance depending on paradigms

  - by Anto

  Is there any data on which paradigms allow for code which is easier/cheaper to maintain? Certainly, independantly of the chosen paradigm, good design is cheaper to maintain than bad, but there should probably be major differences coming only from the paradigm choice. Unstructured programming, for instance, generates very messy code (spaghetti code) which is expensive to maintain. In object oriented programming, implementation details are hidden and thus it should be pretty cheap to change those. In functional programming, there are no side effects, thus there is lesser risk of introducing bugs during maintainance, which should be cheaper. Is there any data on which paradigms are the most cost-efficient when coming down to maintenance? If no such data exists, what is your take on the question?

  Read the article

• What is it going here in my solution?

  - by bbb

  I am a asp.net mvc programmer and if I want to start a project I do this: I make a class library named Model for my models. I make a class library named Infrastructure.Repository for database processes I make a class library named Application for business logic layer And finally I make a MVC project for the UI. But now some things are confusing me. Am I using 3-tier programming? If yes so what is n-tier programming and which one is better? If no so what is 3-tier programming? Some where I see that the tiers namings are DAL and BIZ. Which one is correct according to the naming convention?

  Read the article

• What are the pro/cons of Unity3D as a choice to make games?

  - by jokoon

  We are doing our school project with Unity3d, since they were using Shiva the previous year (which seems horrible to me), and I wanted to know your point of view for this tool. Pros: multi platform, I even heard Google is going to implement it in Chrome everything you need is here scripting languages makes it a good choice for people who are not programming gurus Cons: multiplayer ? proprietary, you are totally dependent of unity and its limit and can't extend it it's less "making a game from scratch" C++ would have been a cool thing I really think this kind of tool is interesting, but is it worth it to use at school for a project that involves more than 3 programming persons ? What do we really learn in term of programming from using this kind of tool (I'm ok with python and js, but I hate C#) ? We could have use Ogre instead, even if we were learning direct x starting january...

  Read the article

• What is the worst programmer habit?

  - by 0x4a6f4672

  Many people get into programming because programming is fun. At least in the beginning. After some time doing it professionally, programming is no longer fun, often just hard work. Sometimes we develop bad habits along the way to make it fun again. Some bad habits of programmers are well known, for example the "I fix that in a second" habit, the "reinvent the wheel" practice or the "all code except mine is crap" attitude (which often leads to "I will re-write the entire program from scratch" syndrome). There are things which a programmer should never do. What is the worst programmer habit?

  Read the article

• Career Shifters: How to compete with IT/ComSci graduates

  - by CareerShifter

  I am wondering what are the chances of a career shifter (mid 20's), who have maybe 3-6 months programming experience vs. younger fresh IT/Com Sci graduates. You see, even though I really love programming (Java/J2EE), but nobody gives me a feedback when I apply online. maybe because they preferred IT/ComSci graduates vs a career shifter like me.. So can you advice on how to improve my chance on being hired. How can i get a real-job programming experince if nobody is hiring me. I can make my own projects (working e-commerce site blah blah) but it is still different from the real job. And my codes are working but it still needs a lot of improvement and no one can tell me how to improve it because no one sees it (because I'm doing it alone?). Do you know any open source websites (java/j2ee/jee) / online home-based jobs who accepts java/j2ee/jee trainees.. Thank you very much

  Read the article

• job offer in dead technology

  - by bold

  I have a job offer in a dead technology (specific programming language) that I don't want to work with nor do I believe it will offer many jobs in the future. It requires twice a year travels abroad, which not a plus in my eyes. On the other hand the money on the table is high. What would you do? edit: as its not clear I got a job in a programming language that is different from the academic programming language I worked with. Now I see it as a mistake to head to that direction.

  Read the article

• Becoming an expert vs boredom [closed]

  - by QAH

  I am a college student, and I love to program, period. I code all kinds of things in different kinds of languages. Although I enjoy programming, I have an extremely hard time sticking to one project for a long time. I attribute this shortcoming to my high level of curiosity, exploring different technologies, languages, libraries, etc. What would be best? Should I settle down more and spend time on becoming an expert in one or two programming fields, or should I be more of a jack of all trades, trying out all kinds of new technologies, languages, programming methods, etc.? I'm guessing that somewhere in the middle would be best. I'm always amazed at how many developers are able to create one or two projects, and develop on them for years. What techniques do you guys employ to help you stay focused on a project?

  Read the article

• I'm a beginner Java programmer but I want to be useful

  - by user105418

  Programming has always interested me, but after learning some of the basics of Java(I'm talking high school level), I don't really know what to do from there. I want to be able to apply what I learned in some way, whether it be a volunteer project or something, but I probably don't know enough programming. Is it possible for a novice Java programmer to be useful in some way whatsoever. I want to do this because I feel like I could learn more about programming by helping people in theirs, but I'm not sure if I'm even able to this though. Does anyone have any suggestions on how I can contribute to other people's project in some way or how to apply it in some way?

  Read the article

• Climbing the hacker ladder

  - by cobie

  This is not a question in which I am asking for opinions rather I am asking for first hand experience. I have been programming in python for quite a while and I feel solid enough in python programming. I can come up with algorithms for problems and implement them but I somehow feel I am stuck with remaining an apprentice. What are some first hand experiences on how to climb up the ladder and become better at programming as in learning about browsers security, compilers etc. Personal experiences would be valued in responses.

  Read the article

• Should I continue to learn and program using ansi c or non standard? [closed]

  - by Erik

  I am a Cs Student, enthusiastic about programming. C is my first programming language that I learned. (Never been exposed to programming, data structures, algorithms before) I failed the exam because I studied on my own and didn't know how to use windows non standard libraries like conio.h. (I had to draw circles, etc using get x and get y). I told them but they just don't care. What do I do because for a beginner this is very confusing? Do I continue to study ansi c on my own, or should I study non standard c? Should I do them in parallel? *I did use the search bar but found nothing useful that could help me.

  Read the article

• Why do we need private variables?

  - by rak

  Why do we need private variables in classes in the context of programming? Every book on programming I've read says this is a private variable, this is how you define it but stops there. The wording of these explanations always seemed to me like we really have a crisis of trust in our profession. The explanations always sounded like other programmers are out to mess up our code. Yet, there are many programming languages that do not have private variables. What do private variables help prevent? How do you decide if a particular of properties should be private or not? If by default every field SHOULD be private then why are there public data members in a class? Under what circumstances should a variable be made public?

  Read the article

• Usefull skills from a computer science degree

  - by Tom Squires

  I did my degree in physics and moved later into programming. I have two and a half years experience under my belt and like to think I write good code. I am, however, concerned that not doing a compsci degree has left holes in my knowledge. I would like to fill those up now since I know I want to be doing programming for the rest of my career. What skills/techniques did you learn in your compsci degree that one wouldn't pick up from on-the-job programming?

  Read the article

• 27 vidéos techniques des Qt DevDays 2005, 2006 et 2008 sont désormais rendues publiques par Qt eLear

  L'équipe eLearning de Qt a depuis quelques temps cherché à récupérer des vidéos techniques issues des conférences des anciens QtDevDays dans l'optique de les faire partager à tout le monde. C'est aujourd'hui chose faite avec la publication en ligne de 27 présentations techniques ce qui correspond à 22h30min de vidéos. Les sujets traités sont toujours valides aujourd'hui, même si le framework a évolué au fil des années. 2005 :All About Qt Widgets Effective Graphics Programming Practical Model/View Programming Threaded Programming with Qt - Good Practise Writing Custom Styles with QStyle Writing plugin applications with Qt 2006 :Advanced Item Views...

  Read the article

• Windows Phone App with 4SQ

  - by Nuttanon Pornpipak

  I'm want to create a my own Coffee shop app for semester's project. It's Windows Phone App. The App can i.e. view who is check-in here now , view menu , view photo by using 4SQ Endpoint APIs. And my problem is I don't know how to start it...which book i should read about C# and I don't know which knowledge (keyword) should i google it i.e. GET POST METHOD , JSON I ever used 4SQ Endpoint APIs once with javascript (jquery) $.ajax{(.....)} to get data from 4SQ Endpoint APIs So I googled and found JSON.NET Class but I don't know how to use it because i never programming in C# I'm just begin programming. I can programming in C only. Thank you Sorry for my bad grammar

  Read the article

• For asp.net mvc is this a three tiered solution?

  - by bbb

  I am a asp.net mvc programmer and if I want to start a project I do this: I make a class library named Model for my models. I make a class library named Infrastructure.Repository for database processes I make a class library named Application for business logic layer And finally I make a MVC project for the UI. But now some things are confusing me. Am I using 3-tier programming? If yes so what is n-tier programming and which one is better? If no so what is 3-tier programming? Some where I see that the tiers namings are DAL and BIZ. Which one is correct according to the naming convention?

  Read the article

• Which C# Book to take?

  - by Fischkopf

  I was searching for a book to learn C#, but now i'm kinda stuck. I found many people asking the same question, and many people gave answers, but there are so many books about C# that it is really hard to decide which one to take. Now i reduced my choice on two books, but I just can't decide between them. Namely, there are: Programming C# 4.0 and C# 4.0 In A Nutshell The first thing I want to know, are these good choices? I'm not completely new to programming, but I just didn't find the right language until know, but i think C# is the one I was searching for. I know all the bassic stuff from Delphi/Java/Python so I think i'm not a complete beginner in programming. Is there anyone out there that read both books and can cleary explain whats the difference between them? I haven't found many reviews and sort of, so I just don't know which one to chose. Or is there any book that is better suiting me?

  Read the article

• WebSocket handshake with Ruby and EM::WebSocket::Server

  - by Chad Johnson

  I am trying to create a simple WebSocket connection in JavaScript against my Rails app. I get the following: WebSocket connection to 'ws://localhost:4000/' failed: Error during WebSocket handshake: 'Sec-WebSocket-Accept' header is missing What am I doing wrong? Here is my code: JavaScript: var socket = new WebSocket('ws://localhost:4000'); socket.onopen = function() { var handshake = "GET / HTTP/1.1\n" + "Host: localhost\n" + "Upgrade: websocket\n" + "Connection: Upgrade\n" + "Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==\n" + "Sec-WebSocket-Protocol: quote\n" + "Sec-WebSocket-Version: 13\n" + "Origin: http://localhost\n"; socket.send(handshake); }; socket.onmessage = function(data) { console.log(data); }; Ruby: require 'rubygems' require 'em-websocket-server' module QuoteService class WebSocket < EventMachine::WebSocket::Server def on_connect handshake_response = "HTTP/1.1 101 Switching Protocols\n" handshake_response << "Upgrade: websocket\n" handshake_response << "Connection: Upgrade\n" handshake_response << "Sec-WebSocket-Accept: HSmrc0sMlYUkAGmm5OPpG2HaGWk=\n" handshake_response << "Sec-WebSocket-Protocol: quote\n" send_message(handshake_response) end def on_receive(data) puts 'RECEIVED: ' + data end end end EventMachine.run do print 'Starting WebSocket server...' EventMachine.start_server '0.0.0.0', 4000, QuoteService::WebSocket puts 'running' end The handshake headers are per Wikipedia.

  Read the article

• php: fopen() of an URL breaks for domain names, not for numerical addresses

  - by b0fh

  After hours of trying to debug a third-party application having trouble with fopen(), i finally discovered that php -r 'echo(file_get_contents("http://www.google.com/robots.txt"));' fails, but php -r 'echo(file_get_contents("http://173.194.32.81/robots.txt"));' Succeeds. Note that as the webserver user, I can ping www.google.com and it resolves just fine. I straced both executions of PHP, and they diverge like this: For the numerical v4 URL: socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 3 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR) fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 connect(3, {sa_family=AF_INET, sin_port=htons(80), sin_addr=inet_addr("173.194 poll([{fd=3, events=POLLOUT}], 1, 0) = 0 (Timeout) ...[bunch of poll/select/recvfrom]... close(3) = 0 For the domain name: socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP) = 3 close(3) = 0 PHP didn't even try to do anything with that socket, it seems. Or even resolve the domain, for that matter. WTF ? Recompiling PHP with or without ipv6 support did not seem to matter. Disabling ipv6 on this system is not desirable. Gentoo Linux, PHP 5.3.14, currently giving a try to PHP 5.4 and see if it helps. Anyone has an idea ? EDIT: php -r 'echo gethostbyname("www.google.com");' Works and yield an ipv4, while php -r 'echo(file_get_contents("http://[2a00:1450:4007:803::1011]/"));' Seems to return a blank result. EDIT 2: I didn't even notice the first time, that the v6 socket opened when the name is used is a SOCK_DGRAM.

  Read the article

• iPhone SDK Push notification randomly fails

  - by Jameson

  I have a PHP file with the following content that works perfectly on development ceritficates, but when I switch to a production certificate the PHP errors and gives the below message, but it only does this about 50% of the time. The other 50% it works. Anyone know why this might be happening? <?php // masked for security reason $deviceToken = 'xxxxxx'; // jq $ctx = stream_context_create(); stream_context_set_option($ctx, 'ssl', 'local_cert', dirname(__FILE__)."/prod.pem"); $number = 5; $fp = stream_socket_client('ssl://gateway.push.apple.com:2195', $err, $errstr, 60, STREAM_CLIENT_CONNECT, $ctx); if (!$fp) { print "Failed to connect $err $errstr\n"; } else { print "Connection OK\n"; $msg = $_GET['msg']; $payload['aps'] = array('alert' => $msg, 'badge' => 1, 'sound' => 'default'); $payload = json_encode($payload); $msg = chr(0) . pack("n",32) . pack('H*', str_replace(' ', '', $deviceToken)) . pack("n",strlen($payload)) . $payload; print "sending message :" . $payload . "\n"; fwrite($fp, $msg); fclose($fp); } ?> The PHP error: Warning: stream_socket_client() [function.stream-socket-client]: Unable to set local cert chain file `/var/www/vhosts/thissite.com/httpdocs/prod.pem'; Check that your cafile/capath settings include details of your certificate and its issuer in /var/www/vhosts/thissite.com/httpdocs/pushMessageLive.php on line 19 Warning: stream_socket_client() [function.stream-socket-client]: failed to create an SSL handle in /var/www/vhosts/thissite.com/httpdocs/pushMessageLive.php on line 19 Warning: stream_socket_client() [function.stream-socket-client]: Failed to enable crypto in /var/www/vhosts/thissite.com/httpdocs/pushMessageLive.php on line 19 Warning: stream_socket_client() [function.stream-socket-client]: unable to connect to ssl://gateway.sandbox.push.apple.com:2195 (Unknown error) in /var/www/vhosts/thissite.com/httpdocs/pushMessageLive.php on line 19 Failed to connect 0

  Read the article

• C# TCP Async EndReceive() throws InvalidOperationException ONLY on Windows XP 32-bit

  - by James Farmer

  I have a simple C# Async Client using a .NET socket that waits for timed messages from a local Java server used for automating commands. The messages come in asynchronously and is written to a ring buffer. This implementation seems to work fine on Windows Vista/7/8 and OSX, but will randomly throw this exception while it's receiving a message from the local Java server: Unhandled Exception: System.InvalidOperationException: EndReceive can only be called once for each asynchronous operation.     at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult, SocketError& errorCode)     at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult)     at SocketTest.Controller.RecvAsyncCallback(IAsyncResult ar)     at System.Net.LazyAsyncResult.Complete(IntPtr userToken)     ... I've looked online for this error, but have found nothing really helpful. This is the code where it seems to break: /// <summary> /// Callback to receive socket data /// </summary> /// <param name="ar">AsyncResult to pass to End</param> private void RecvAsyncCallback(IAsyncResult ar) { // The exception will randomly happen on this call int bytes = _socket.EndReceive(_recvAsyncResult); // check for connection closed if (bytes == 0) { return; } _ringBuffer.Write(_buffer, 0, bytes); // Checks buffer CheckBuffer(); _recvAsyncResult = _sock.BeginReceive(_buffer, 0, _buffer.Length, SocketFlags.None, RecvAsyncCallback, null); } The error doesn't happen on any particular moment except in the middle of receiving a message. The message itself can be any length for this to happen, and the exception can happen right away, or sometimes even up to a minute of perfect communication. I'm pretty new with sockets and network communication, and I feel I might be missing something here. I've tested on at least 8 different computers, and the only similarity with the computers that throw this exception is that their OS is Windows XP 32-bit.

  Read the article

• Unable to aquire image through ImageIO.read(url) because of connection timed out.

  - by Jake Frederix

  Following code always fails URL url = new URL("http://userserve-ak.last.fm/serve/126/8636005.jpg"); Image img = ImageIO.read(url); System.out.println(img); I've manually checked the url, and it is valid, and contains a valid jpg image. The problem I get is; Exception in thread "main" javax.imageio.IIOException: Can't get input stream from URL! at javax.imageio.ImageIO.read(ImageIO.java:1385) at maestro.Main2.main(Main2.java:25) Caused by: java.net.ConnectException: Connection timed out at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:310) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:176) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:163) at java.net.Socket.connect(Socket.java:546) at java.net.Socket.connect(Socket.java:495) at sun.net.NetworkClient.doConnect(NetworkClient.java:174) at sun.net.www.http.HttpClient.openServer(HttpClient.java:409) at sun.net.www.http.HttpClient.openServer(HttpClient.java:530) at sun.net.www.http.HttpClient.(HttpClient.java:240) at sun.net.www.http.HttpClient.New(HttpClient.java:321) at sun.net.www.http.HttpClient.New(HttpClient.java:338) at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:814) at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:755) at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:680) at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1005) at java.net.URL.openStream(URL.java:1029) at javax.imageio.ImageIO.read(ImageIO.java:1383) ... 1 more Java Result: 1 What does this mean? Funny thing is, if I change my internet-connection to that of the neighbour's wireless, it suddenly does work.

  Read the article

• Why is it assumed that send may return with less than requested data transmitted on a blocking socke

  - by Ernelli

  The standard method to send data on a stream socket has always been to call send with a chunk of data to write, check the return value to see if all data was sent and then keep calling send again until the whole message has been accepted. For example this is a simple example of a common scheme: int send_all(int sock, unsigned char *buffer, int len) { int nsent; while(len 0) { nsent = send(sock, buffer, len, 0); if(nsent == -1) // error return -1; buffer += nsent; len -= nsent; } return 0; // ok, all data sent } Even the BSD manpage mentions that ...If no messages space is available at the socket to hold the message to be transmitted, then send() normally blocks... Which indicates that we should assume that send may return without sending all data. Now I find this rather broken but even W. Richard Stevens assumes this in his standard reference book about network programming, not in the beginning chapters, but the more advanced examples uses his own writen (write all data) function instead of calling write. Now I consider this still to be more or less broken, since if send is not able to transmit all data or accept the data in the underlying buffer and the socket is blocking, then send should block and return when the whole send request has been accepted. I mean, in the code example above, what will happen if send returns with less data sent is that it will be called right again with a new request. What has changed since last call? At max a few hundred CPU cycles have passed so the buffer is still full. If send now accepts the data why could'nt it accept it before? Otherwise we will end upp with an inefficient loop where we are trying to send data on a socket that cannot accept data and keep trying, or else? So it seems like the workaround, if needed, results in heavily inefficient code and in those circumstances blocking sockets should be avoided at all an non blocking sockets together with select should be used instead.

  Read the article

• C++ boost.asio server and client connection undersanding

  - by Edgar Buchvalov

  i started learning boost.asio and i have some problems with undersanding tcp connections. There is example from official boost site: #include <ctime> #include <iostream> #include <string> #include <boost/asio.hpp> using boost::asio::ip::tcp; std::string make_daytime_string() { using namespace std; // For time_t, time and ctime; time_t now = time(0); return ctime(&now); } int main() { try { boost::asio::io_service io_service; tcp::acceptor acceptor(io_service, tcp::endpoint(tcp::v4(), 13)); for (;;) { tcp::socket socket(io_service); acceptor.accept(socket); std::string message = make_daytime_string(); boost::system::error_code ignored_error; boost::asio::write(socket, boost::asio::buffer(message), boost::asio::transfer_all(), ignored_error); } } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } there is question, why if i want to connet to this server via client i have t write: boost::asio::io_service io_service; tcp::resolver resolver(io_service); tcp::resolver::query query(host_ip, "daytime"); //why daytime? tcp::resolver::iterator endpoint_iterator = resolver.resolve(query); tcp::resolver::iterator end; why daytime?, what it meant and where it is inicialized in server, or i just doesn't missed somefing? there is full client code : www.boost.org/doc/libs/1_39_0/doc/html/boost_asio/tutorial/tutdaytime1.html thanks for explanation in advance

  Read the article

• eclipseFP2 haskell unix haveing issues connectiong to Scion Server

  - by Chris

  I am having troubles with using FP2 for eclipse and getting it to connect with the server. Eclipse seems to auto-detect scion_server, but I a error in the log file !ENTRY net.sf.eclipsefp.haskell.scion.client 4 4 2010-04-15 10:40:06.580 !MESSAGE The connection with the Scion server could not be established. !STACK 0 The connection with the Scion server could not be established. at net.sf.eclipsefp.haskell.scion.internal.client.ScionServer.connectToServer(ScionServer.java:328) at net.sf.eclipsefp.haskell.scion.internal.client.ScionServer.startServer(ScionServer.java:73) at net.sf.eclipsefp.haskell.scion.client.ScionInstance.start(ScionInstance.java:94) at net.sf.eclipsefp.haskell.scion.client.ScionInstance.runCommandSync(ScionInstance.java:207) at net.sf.eclipsefp.haskell.scion.internal.commands.ScionCommand.run(ScionCommand.java:136) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55) Caused by: java.net.ConnectException: Connection refused at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(Unknown Source) at java.net.PlainSocketImpl.connectToAddress(Unknown Source) at java.net.PlainSocketImpl.connect(Unknown Source) at java.net.SocksSocketImpl.connect(Unknown Source) at java.net.Socket.connect(Unknown Source) at java.net.Socket.connect(Unknown Source) at java.net.Socket.<init>(Unknown Source) at java.net.Socket.<init>(Unknown Source) at net.sf.eclipsefp.haskell.scion.internal.client.ScionServer.connectToServer(ScionServer.java:345) at net.sf.eclipsefp.haskell.scion.internal.client.ScionServer.connectToServer(ScionServer.java:324)

  Read the article

< Previous Page | 255 256 257 258 259 260 261 262 263 264 265 266  | Next Page >