Search Results

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

Page 423/616 | < Previous Page | 419 420 421 422 423 424 425 426 427 428 429 430  | Next Page >

  • Could anyone tell me something about Scheme Common-Lisp and FASL File.

    - by Joe
    Does anyone could tell something about these file? As I know: 1. Common-Lisp and Scheme are both some lisp programming langue. 2. common-Lisp source file *.lisp can be compiled into binary file *.fasl which can be load faster than the source file. Q:Can the Scheme source code *.scm be compiled into some binary file that will be load faster than the source code? Thanks in advance joe

    Read the article

  • Any application to bind documents of different kind

    - by Codeslayer
    A situation that may be quite common in offices is: We communicate with clients over e-mails, exchange documents and spreadsheets with them. Is there any tool which will help me in binding all these outputs. Maybe I may get flamed on this as this is not exactly a programming question. But some inputs may certainly help me. Thanx

    Read the article

  • How can i attach to a process using gdbvim?

    - by thamurath
    Hi, I use Vim as primary IDE for programming, with some plugins i have a good environment but for a single point: debugging. I have recompiled Vim to use vimgdb, and it works, but the problem is that i need to attach to a process started by a root user so i have to use sudo to do it.... How can i do this with vimgdb? Thanks in advance.

    Read the article

  • how to print a char from struct

    - by make
    Hi Could someone please tell us to print a char when receiving data as a struct? Here is an example: ... struct rcv{ int x1; float x2; char *x3; }; rcv data_rcv; ... if (recv(socket, &data_rcv, sizeof(data_rcv), 0) < 0) printf("recv() failed"); ... printf("x1 = %d\n", data_rcv.x1); printf("x2 = %f\n", data_rcv.x2); printf("x3 = %s\n", data_rcv.x3); // it doesn't print anything, why? ... Thanks for your replies-

    Read the article

  • Pitfalls when switching to .NET for Windows CE?

    - by Presidenten
    Hi! I have been developing in .NET for quite some time now. But now I have customer who wants me to develop an application for them in .NET for Windows CE. I have done some embedded system programming in C before, but never in .NET. Please share any tips or tricks that would make my life easier when taking this assignment, or perhaps knowledge about any pitfalls to watch out for.

    Read the article

  • Simplifying const Overloading?

    - by templatetypedef
    Hello all- I've been teaching a C++ programming class for many years now and one of the trickiest things to explain to students is const overloading. I commonly use the example of a vector-like class and its operator[] function: template <typename T> class Vector { public: T& operator[] (size_t index); const T& operator[] (size_t index) const; }; I have little to no trouble explaining why it is that two versions of the operator[] function are needed, but in trying to explain how to unify the two implementations together I often find myself wasting a lot of time with language arcana. The problem is that the only good, reliable way that I know how to implement one of these functions in terms of the other is with the const_cast/static_cast trick: template <typename T> const T& Vector<T>::operator[] (size_t index) const { /* ... your implementation here ... */ } template <typename T> T& Vector<T>::operator[] (size_t index) { return const_cast<T&>(static_cast<const Vector&>(*this)[index]); } The problem with this setup is that it's extremely tricky to explain and not at all intuitively obvious. When you explain it as "cast to const, then call the const version, then strip off constness" it's a little easier to understand, but the actual syntax is frightening,. Explaining what const_cast is, why it's appropriate here, and why it's almost universally inappropriate elsewhere usually takes me five to ten minutes of lecture time, and making sense of this whole expression often requires more effort than the difference between const T* and T* const. I feel that students need to know about const-overloading and how to do it without needlessly duplicating the code in the two functions, but this trick seems a bit excessive in an introductory C++ programming course. My question is this - is there a simpler way to implement const-overloaded functions in terms of one another? Or is there a simpler way of explaining this existing trick to students? Thanks so much!

    Read the article

  • void foo(int &x) -> Ruby? Passing integers by reference?

    - by Earlz
    Hello, as a way to spice up my C++ programming homework, I've decided to instead of typing the C++ from the book onto my computer, instead reforming it in Ruby. Yes it's a bit silly, but I'm bored. Anyway, I'm having trouble converting this kind of function to Ruby void swap(int &a,int &b){ int c=b; b=a; a=c } What would the equivalent ruby code looking inside a function ?

    Read the article

  • Is multithreading the right way to go for my case?

    - by Julien Lebosquain
    Hello, I'm currently designing a multi-client / server application. I'm using plain good old sockets because WCF or similar technology is not what I need. Let me explain: it isn't the classical case of a client simply calling a service; all clients can 'interact' with each other by sending a packet to the server, which will then do some action, and possible re-dispatch an answer message to one or more clients. Although doable with WCF, the application will get pretty complex with hundreds of different messages. For each connected client, I'm of course using asynchronous methods to send and receive bytes. I've got the messages fully working, everything's fine. Except that for each line of code I'm writing, my head just burns because of multithreading issues. Since there could be around 200 clients connected at the same time, I chose to go the fully multithreaded way: each received message on a socket is immediately processed on the thread pool thread it was received, not on a single consumer thread. Since each client can interact with other clients, and indirectly with shared objects on the server, I must protect almost every object that is mutable. I first went with a ReaderWriterLockSlim for each resource that must be protected, but quickly noticed that there are more writes overall than reads in the server application, and switched to the well-known Monitor to simplify the code. So far, so good. Each resource is protected, I have helper classes that I must use to get a lock and its protected resource, so I can't use an object without getting a lock. Moreover, each client has its own lock that is entered as soon as a packet is received from its socket. It's done to prevent other clients from making changes to the state of this client while it has some messages being processed, which is something that will happen frequently. Now, I don't just need to protect resources from concurrent accesses. I must keep every client in sync with the server for some collections I have. One tricky part that I'm currently struggling with is the following: I have a collection of clients. Each client has its own unique ID. When a client connects, it must receive the IDs of every connected client, and each one of them must be notified of the newcomer's ID. When a client disconnects, every other client must know it so that its ID is no longer valid for them. Every client must always have, at a given time, the same clients collection as the server so that I can assume that everybody knows everybody. This way if I'm sending a message to client #1 telling "Client #2 has done something", I know that it will always be correctly interpreted: Client 1 will never wonder "but who is Client 2 anyway?". My first attempt for handling the connection of a new client (let's call it X) was this pseudo-code (remember that newClient is already locked here): lock (clients) { foreach (var client in clients) { lock (client) { client.Send("newClient with id X has connected"); } } clients.Add(newClient); newClient.Send("the list of other clients"); } Now imagine that in the same time, another client has sent a packet that translates into a message that must be broadcasted to every connected client, the pseudo-code will be something like this (remember that the current client - let's call it Y - is already locked here): lock (clients) { foreach (var client in clients) { lock (client) { client.Send("something"); } } } An obvious deadlock occurs here: on one thread X is locked, the clients lock has been entered, started looping through the clients, and at one moment must get Y's lock... which is already acquired on the second thread, itself waiting for the clients collection lock to be released! This is not the only case like this in the server application. There are other collections which must be kept in sync with the clients, some properties on a client can be changed by another one, etc. I tried other types of locks, lock-free mechanisms and a bunch of other things. Either there were obvious deadlocks when I'm using too much locks for safety, or obvious race conditions otherwise. When I finally find a good middle point between the two, it usually comes with very subtle race conditions / dead locks and other multi-threading issues... my head hurts very quickly since for any single line of code I'm writing I have to review almost the whole application to ensure everything will behave correctly with any number of threads. So here's my final question: how would you resolve this specific case, the general case, and more importantly: aren't I going the wrong way here? I have little problems with the .NET framework, C#, simple concurrency or algorithms in general. Still, I'm lost here. I know I could use only one thread processing the incoming requests and everything will be fine. However, that won't scale well at all with more clients... But I'm thinking more and more to go this simple way. What do you think? Thanks in advance to you, StackOverflow people which have taken the time to read this huge question. I really had to explain the whole context if I want to get some help.

    Read the article

  • Webcam capture with c# and convert to avi

    - by Spidfire
    Im trying to make a program that captures a video from the webcam and sound from the microphone but im getting stuck at the part where ive try to make a movie out of still images ive heard you need to use directshow but it doesnt jet work for me Does someone know a good piece of example code that captures video and sound and can encode it to a file (divx or something like that) ? or some suggestions where to look so i can build it myself (if a other programming language is better for this im happy to know it early. )

    Read the article

  • General advice from people in the industry - new graduate

    - by confusified
    I'm 20 years old and have just finished a 4 year Information Technology degree in Ireland, The main focus of the course was programming (mainly java) and software engineering. My question (posted in the wrong place as it may be) is : What technologies that I may not have studied should I attempt to teach myself that will be of the most benefit to me in searching for employment? All input appreciated.

    Read the article

  • Is it common practice to put keywords in html markup for SEO?

    - by Joel
    Though it's on the edge of programming questions, I think this is still relevant here, as only those of us actually doing the coding for a site would be considering this. I've been reading more about keyword placement, and it seems to me like a good place to do keyword placement would be in the class and id names chosen for the elements they are representing. I'm not talking about any kind of black-hat keyword stuffing thing but real legitimate use of descriptive keywords for elements. Is this something that is actively done for SEO?

    Read the article

  • How to extract the data from a website using java?

    - by giri
    Hi I am familier with java programming language I like to extract the data from a website and store it to my database running on my machine.Is that possible in java.If so which API I should use. For example the are number of schools listed on a website How can I extract that data and store it to my database using java.

    Read the article

  • ubuntu on virtual machine vs ubuntu install, what the difference?

    - by Yosef
    Hi, I have windows xp in my work and i programming on zend framework. I need to install ubuntu for execute doctrine orm commands from linux console, I faile to do it on windows. I thinking about 2 option of UBUNTU installation: 1.install ubuntu 10.04 on Virtual Box (Sun Virtual Machine). 2.create new primary partition and install ubuntu 10.04 directly. Which options do you suggest to do? Thanks

    Read the article

  • Where can I find a web-project "security checklist?"

    - by iaagty
    I'm looking for a complete list of security guidelines for programming and deploying PHP web sites and applications on an Apache (Linux) server. Basically, a "security check list" to run through before finishing a project. I.e., Cross Site Scripting Cross Site Request Forgery Sanitize form data that goes into database Disable register globals and error reporting in custom php.ini Upload files below web root ...(the list goes on) I did some searching on the internet and in this forum, but couldn't find a comprehensive, succinct, and complete list of guidelines. Thanks in advance.

    Read the article

  • What are the list of Patterns and Principals the programmer must/should know?

    - by pang
    I have been doing code for a few years and still feeling that my knowledge still not broad enough to become a professional. I have studied some books related to Design Pattern but I know there are many others. So could anyone list the one which you think it is good to learn to become a better programmer and more professional? Programming Languages I work on : C# , Ruby, Javascript

    Read the article

< Previous Page | 419 420 421 422 423 424 425 426 427 428 429 430  | Next Page >