Search Results

Search found 16032 results on 642 pages for 'everyday problems'.

Page 537/642 | < Previous Page | 533 534 535 536 537 538 539 540 541 542 543 544  | Next Page >

  • Creating and appending a big DOM with javascript - most optimized way?

    - by fenderplayer
    I use the following code to append a big dom on a mobile browser (webkit): 1. while(someIndex--) // someIndex ranges from 10 to possibly 1000 2. { 3. var html01 = ['<div class="test">', someVal,'</div>', 4. '<div><p>', someTxt.txt1, someTxt.txt2, '</p></div>', 5. // lots of html snippets interspersed with variables 6. // on average ~40 to 50 elements in this array 7. ].join(''); 8. var fragment = document.createDocumentFragment(), 9. div = fragment.appendChild(document.createElement('div')); 10. div.appendChild(jQuery(html01)[0]); 11. jQuery('#screen1').append(fragment); 12. } //end while loop 13. // similarly i create 'html02' till 'html15' to append in other screen divs Is there a better or faster way to do the above? Do you see any problems with the code? I am a little worried about line 10 where i wrap in jquery and then take it out.

    Read the article

  • How To Update EF 4 Entity In ASP.NET MVC 3?

    - by Jason Evans
    Hi there. I have 2 projects - a class library containing an EDM Entity Framework model and a seperate ASP.NET MVC project. I'm having problems with how your suppose to edit and save changes to an entity using MVC. In my controller I have: public class UserController : Controller { public ActionResult Edit(int id) { var rep = new UserRepository(); var user = rep.GetById(id); return View(user); } [HttpPost] public ActionResult Edit(User user) { var rep = new UserRepository(); rep.Update(user); return View(user); } } My UserRepository has an Update method like this: public void Update(User user) { using (var context = new PDS_FMPEntities()) { context.Users.Attach(testUser); context.ObjectStateManager.ChangeObjectState(testUser, EntityState.Modified); context.SaveChanges(); } } Now, when I click 'Save' on the edit user page, the parameter user only contains two values populated: Id, and FirstName. I take it that is due to the fact that I'm only displaying those two properties in the view. My question is this, if I'm updating the user's firstname, and then want to save it, what am I suppose to do about the other User properties which were not shown on the view, since they now contain 0 or NULL values in the user object? I've been reading a lot about using stub entities, but I'm getting nowhere fast, in that none of the examples I've seen actually work. i.e. I keep getting EntityKey related exceptions. Can someone point me to a good tutorial/example of how to update EF 4 entities using a repository class, called by an MVC front-end? Cheers. Jas.

    Read the article

  • Resharper 5: How do I set the default formatting style for inline code blocks?

    - by nukefusion
    I've got a problem with the formatting of inline code blocks within the VS2010 text editor and wonder if anyone else has had similar problems and found the 'magic' setting I'm looking for. I'm working my way through tutorials in an MVC book. Whenever I add some inline code blocks to a view I want them formatted like so: <% foreach (var link in Model) { %> <a href="<%=Url.RouteUrl(link.RouteValues)%>"> <%=link.Text%> </a> <% } %> What I'm actually getting is this (auto-formatted by the IDE when I finish writing the code): <% foreach (var link in Model) { %> <a href="<%=Url.RouteUrl(link.RouteValues)%>"> <%=link.Text%> </a> <% } %> It's pretty irritating. Any ideas on how I can instruct the IDE to leave my <% % tags alone? I've been fiddling with options under "Tools - Options - Text Editor" for ages but alas am getting nowhere... Edit: I've just noticed that this is down to Resharper 5 (when I disable it the problem disappears), however I still don't know how to stop it. Any ideas?

    Read the article

  • Does "delegate" mean a type or an object?

    - by Michal Czardybon
    Reading from MSDN: "A delegate is a type that references a method. Once a delegate is assigned a method, it behaves exactly like that method." Does then "delegate" mean a type or an object?! ...It cannot be both. It seems to me that the single word is used in two different meanings: a type containing a reference to a method of some specified signature, an object of that type, which can be actually called like a method. I would prefer a more precise vocabulary and use "delegate type" for the first case. I have been recently reading a lot about events and delegates and that ambiguity was making me confused many times. Some other uses of "delegate" word in MSDN in the first meaning: "Custom event delegates are needed only when an event generates event data" "A delegate declaration defines a class that is derived from the class System.Delegate" Some other uses of "delegate" word in MSDN in the second meaning: "specify a delegate that will be called upon the occurrence of some event" "Delegates are objects that refer to methods. They are sometimes described as type-safe function pointers" What do you think? Why did people from Microsoft introduced this ambiguity? Am I the only person to have conceptual problems with different notions being referenced with the same word.

    Read the article

  • CSS - vertical align text where text can be multiple lines

    - by Sniffer
    Hi all I've been given a design by a graphic designer, which I'm trying to put into HTML and CSS. One of the issues I'm facing is on a user input form. In the design the labels for each input are a fixed width - say 100px. The container for each label/input pair is fixed at 2em. The design I've been given has asked that the text for each label is vertically aligned. So the structure is like this: <containerTag> <label /> <input /> </containerTag> No problems as long as the text is on one line (I would have just used line-height of 2em to match the container), but some of the text in the labels are wrapping to two or even lines. Is there a semantic and nice way to get around this problem? I need something that will work in IE6-9, Firefox 3.5+, Chrome and Safari. Although I am using progressive enhancement, so if there is a solution that will only work on the later browsers, but won't break the older ones, then this would be acceptable. Any help gratefully received! Thanks for your time S

    Read the article

  • How to make a div extend when floating it?

    - by cjmcjm
    I'm trying to create a bar with a dynamic horizontal width. The backgrounds are transparent pngs so they can't overlap. I have one for the left side, one to repeat-x across the dynamic width middle and then another bg for the right. Here is kinda what I have so far... .bar{ width: 100%; } .left{ width: 50px; height: 50px; float: left; } .mid{ height: 50px; float: left; } .right{ width: 50px; height: 50px; float: right; } <div class="bar"> <div class="left"></div> <div class="mid"></div> <div class="right"></div> </div> So the main problem is extending the .mid all the way across to meet the right, width: 100% doesn't work. The other problems is what can I do if I have content that needs to overlap the .left and .mid divs? Set up another div and use z-index? Thanks so much!

    Read the article

  • Asp.net mvc inheritance controllers

    - by Ris90
    Hi, I'm studing asp.net mvc and in my test project I have some problems with inheritance: In my model I use inheritanse in few entities: public class Employee:Entity { /* few public properties */ } It is the base class. And descendants: public class RecruitmentOfficeEmployee: Employee { public virtual RecruitmentOffice AssignedOnRecruitmentOffice { get; set; } } public class ResearchInstituteEmployee: Employee { public virtual ResearchInstitute AssignedOnResearchInstitute { get; set; } } I want to implement a simple CRUD operations to every descedant. What is the better way to inplement controllers and views in descendants: - One controller per every descendant; - Controller inheritance; - Generic controller; - Generic methods in one controller. Or maybe there is an another way? My ORM is NHibernate, I have a generic base repository and every repository is its descedant. Using generic controller, I think, is the best way, but in it I will use only generic base repository and extensibility of the system will be not very good. Please, help the newbie)

    Read the article

  • HTML, CSS: overbar matching square root symbol

    - by Pindatjuh
    Is there a way in HTML and/or CSS to do the following, but then correctly: √¯¯¯¯¯¯φ·(2π−γ) Such that there is an overbar above the expression, which neatly aligns with the &radic;? I know there is the Unicode &macr;, that looks like the overbar I need (as used in the above example, though as you can see – it doesn't align well with the root symbol). The solution I'm looking for works at least for one standard font, on most sizes, and all modern browsers. I can't use images; I'd like to have a pure HTML4/CSS way, without client scripting. Here is my current code, thank you Matthew Jones (+1) for the text-decoration: overline! Still some problems <div style="font-family: Georgia; font-size: 200%"> <span style="vertical-align: -15%;">&radic;</span><span style="text-decoration: overline;">&nbsp;x&nbsp;+&nbsp;1&nbsp;</span> </div> The line doesn't match the &radic; because I lowered it with 15% baseline height. (Because the default placement is not nice) The line thickness doesn't match the thickness of the &radic;. Thanks!

    Read the article

  • Saving temporary file name after uploading file with uplodify

    - by mIRU
    I have this script if (!empty($_FILES)) { $tempFile = $_FILES['Filedata']['tmp_name']; $targetPath = dirname(__FILE__).$_POST['folder'] . '/'; $pathinfoFile = pathinfo($_FILES['Filedata']['name']); $targetFile = str_replace('//','/',$targetPath) .uniqid().'.'.$pathinfoFile['extension']; move_uploaded_file($tempFile,$targetFile); } this script is from uplodify , modified for saving the file with unique name , i need after user will upload the file , this unique name and original name , to save temporary , when user will submit the form , this temporary variables i will insert in database , the problem is that in firebug console , i can not see all the actions of this script , and i can not understand the way how to fix it, I tried to save in $_SESSION but i have problems , is not saving , i found why is not working with $_SESSION , http://uploadify.com/forum/viewtopic.php?f=5&t=43 , i tried the solution from forum but without result , exist a more easy way to solve this problem ? , or what is better way to do it ? . Sorry for so silly question , i ran out of ideas . Thanks a lot for helping me , and sorry again for my English

    Read the article

  • Authentication Problem in Silverlight - Cannot connect to SQL Server

    - by Johann
    Hi All, At the moment, when I try to register a user using the default Business Template in Silverlight, I am getting an error. Basically I am following a tutorial found on Channel 9 on how to build a business app with Silverlight. "An error has occurred while establishing a connection to the server. (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 5) An error has occurred while establishing a connection to the server. When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 1326)". I found a blog where it identifies the problem, and followed every step, however I am still getting the same problems. Here is my connection string:- <add name="SIEventManagerEntities" connectionString="metadata=res://*/EventManagerDBModel.csdl|res://*/EventManagerDBModel.ssdl|res://*/EventManagerDBModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=MONFU-PC;Initial Catalog=SIEventManager;Integrated Security=SSPI;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" /> Any help would really be very much appreciated! Thanks

    Read the article

  • Cross domain javascript to access localhost. Possible?

    - by Earlz
    Hello, for one reason or another I need for javascript to access a webserver on the localhost. This localhost webserver is under our control so we can have whatever software running in it. How would you do this? I've seen things like YQL but this accesses another domain from the internet. This kind of access causes a lot of problems with firewalls and such. So I want to access the same computer that the browser is running on. How would you do this with javascript and whatever software running on the localhost server? Also, the javascript is being run from an internet site. And the localhost server will not be running on the same port are the internet website is. Is this possible to do? I know about the cross-domain restrictions but I've also seen there are ways around them such as YQL. How does something like YQL work? How would you reimplement it?

    Read the article

  • SASS mixin for swapping images / floats on site language (change)

    - by DBUK
    Currently using SASS on a website build. It is my first project using it, tried a little LESS before and liked it. I made a few basic mixins and variables with LESS, super useful stuff! I am trying to get my head around SASS mixins, and syntax, specifically for swapping images when the page changes to a different language, be that with body ID changing or <html lang="en">. And, swapping floats around if, for example, a website changed to chinese. So a mixin where float left is float left unless language is AR and then it becomes float right. With LESS I think it would be something like: .headerBg() when (@lang = en) {background-image:url(../img/hello.png);} .headerBg() when (@lang = it) {background-image:url(../img/ciao.png);} .header {.headerBg(); width: 200px; height:100px} .floatleft() when (@lang = en) { float: left;} .floatleft() when (@lang = ar) { float: right;} .logo {.floatleft();} Its the syntax I am having problems with combined with a brain melting day.

    Read the article

  • Are there good reasons not to use an ORM?

    - by hangy
    During my apprenticeship, I have used NHibernate for some smaller projects which I mostly coded and designed on my own. Now, before starting some bigger project, the discussion arose how to design data access and whether or not to use an ORM layer. As I am still in my apprenticeship and still consider myself a beginner in enterprise programming, I did not really try to push in my opinion, which is that using an object relational mapper to the database can ease development quite a lot. The other coders in the development team are much more experienced than me, so I think I will just do what they say. :-) However, I do not completely understand two of the main reasons for not using NHibernate or a similar project: One can just build one’s own data access objects with SQL queries and copy those queries out of Microsoft SQL Server Management Studio. Debugging an ORM can be hard. So, of course I could just build my data access layer with a lot of SELECTs etc, but here I miss the advantage of automatic joins, lazy-loading proxy classes and a lower maintenance effort if a table gets a new column or a column gets renamed. (Updating numerous SELECT, INSERT and UPDATE queries vs. updating the mapping config and possibly refactoring the business classes and DTOs.) Also, using NHibernate you can run into unforeseen problems if you do not know the framework very well. That could be, for example, trusting the Table.hbm.xml where you set a string’s length to be automatically validated. However, I can also imagine similar bugs in a “simple” SqlConnection query based data access layer. Finally, are those arguments mentioned above really a good reason not to utilise an ORM for a non-trivial database based enterprise application? Are there probably other arguments they/I might have missed? (I should probably add that I think this is like the first “big” .NET/C# based application which will require teamwork. Good practices, which are seen as pretty normal on Stack Overflow, such as unit testing or continuous integration, are non-existing here up to now.)

    Read the article

  • Managing libraries and imports in a programming language

    - by sub
    I've created an interpreter for a stupid programming language in C++ and the whole core structure is finished (Tokenizer, Parser, Interpreter including Symbol tables, core functions, etc.). Now I have a problem with creating and managing the function libraries for this interpreter (I'll explain what I mean with that later) So currently my core function handler is horrible: // Simplified version myLangResult SystemFunction( name, argc, argv ) { if ( name == "print" ) { if( argc < 1 ) { Error('blah'); } cout << argv[ 0 ]; } else if ( name == "input" ) { if( argc < 1 ) { Error('blah'); } string res; getline( cin, res ); SetVariable( argv[ 0 ], res ); } else if ( name == "exit ) { exit( 0 ); } And now think of each else if being 10 times more complicated and there being 25 more system functions. Unmaintainable, feels horrible, is horrible. So I thought: How to create some sort of libraries that contain all the functions and if they are imported initialize themselves and add their functions to the symbol table of the running interpreter. However this is the point where I don't really know how to go on. What I wanted to achieve is that there is e.g.: an (extern?) string library for my language, e.g.: string, and it is imported from within a program in that language, example: import string myString = "abcde" print string.at( myString, 2 ) # output: c My problems: How to separate the function libs from the core interpreter and load them? How to get all their functions into a list and add it to the symbol table when needed? What I was thinking to do: At the start of the interpreter, as all libraries are compiled with it, every single function calls something like RegisterFunction( string namespace, myLangResult (*functionPtr) ); which adds itself to a list. When import X is then called from within the language, the list built with RegisterFunction is then added to the symbol table. Disadvantages that spring to mind: All libraries are directly in the interpreter core, size grows and it will definitely slow it down.

    Read the article

  • Giving writing permissions for IIS user at Windows 2003 Server

    - by Steve
    I am running a website over Windows 2003 Server and IIS6 and I am having problems to write or delete files in some temporary folder obtaining this kind of warmings: Warning: unlink(C:\Inetpub\wwwroot\cakephp\app\tmp\cache\persistent\myapp_cake_core_cake_): Permission denied in C:\Inetpub\wwwroot\cakephp\lib\Cake\Cache\Engine\FileEngine.php on line 254 I went to the tmp directory and at the properties I gave the IIS User the following permissions: Read & Execute List folder Contents Read And it still showing the same warnings. When I am on the properties window, if I click on Advanced the IIS username appears twice. One with Allow type and read & execute permissions and the other with Deny type and Special permissions. My question is: Should I give this user not only the Read & Execute permissions but also this ones?: Create Attributes Create Files/ Write Data Create Folders/ Append Data Delete Subfolders and Files Delete They are available to select if I Click on the edit button over the username. Wouldn't I be opening a security hole if I do this? Otherwise, how can I do to read and delete the files my website uses? Thanks.

    Read the article

  • C++ Initialize array in constructor EXC_BAD_ACCESS

    - by user890395
    I'm creating a simple constructor and initializing an array: // Construtor Cinema::Cinema(){ // Initalize reservations for(int i = 0; i < 18; i++){ for(int j = 0; j < 12; j++){ setReservation(i, j, 0); } } // Set default name setMovieName("N/A"); // Set default price setPrice(8); } The setReservation function: void Cinema::setReservation(int row, int column, int reservation){ this->reservations[row][column] = reservation; } The setMovieName function: void Cinema::setMovieName(std::string movieName){ this->movieName = movieName; } For some odd reason when I run the program, the setMovieName function gives the following error: "Program Received Signal: EXC_BAD_ACCESS" If I take out the for-loop that initializes the array of reservations, the problem goes away and the movie name is set without any problems. Any idea what I'm doing wrong? This is the Cinema.h file: #ifndef Cinema_h #define Cinema_h class Cinema{ private: int reservations[17][11]; std::string movieName; float price; public: // Construtor Cinema(); // getters/setters int getReservation(int row, int column); int getNumReservations(); std::string getMovieName(); float getPrice(); void setReservation(int row, int column, int reservation); void setMovieName(std::string movieName); void setPrice(float price); }; #endif

    Read the article

  • JQuery - Set TBODY

    - by Villager
    Hello, I have a table defined as follows: <table id="myTable" cellpadding="0" cellspacing="0"> <thead><tr> <th>Date</th> <th>First Name</th> <th>Last Name</th> </tr></thead> <tbody> <!-- rows will go here --> </tbody> </table> I am trying to dynamically populate 'myTable' at runtime via JavaScript. To accomodate for this, I am using JQuery. I want to write some HTML into the tbody element within 'myTable'. However, I am having problems understanding how to do this with the selectors. I know that I can get 'myTable' using: $("#myTable") I know that I can set the HTML of myTable by using the following: $("#myTable").html(someHtmlString); However, that sets the HTML of the entire table. In reality, I just want to set the HTML within the TBODY of 'myTable'. How do I do this with JQuery? Thank you!

    Read the article

  • Deployment a web-site on IIS from another program

    - by slo2ols
    Hi, I developed a web-site on ASP.NET 3.5 SP1 platform. And additional I have 2 win services. My task is to build install package. I decided that Visual Studio install projects are not met my requirements. I design my own installer for this project, because I need to resolve many question and problem in install process. My problem: I need to deploy web-site into IIS, but I don't know how to do it easy. I found Microsoft tool as Web Deployment Tool, but I didn't find any documentation. And must I include this tool into my installer for deployment at destination customer? Another side I found SDC Tasks Library and it looks like a solution for me. But I saw many topics where people had problems and because the project was dead anybody couldn't help them. I know it is a long story... My question: how can I deploy the web-site from another program (I know that IIS versions have some differences and it is another headache), set a virtual directory, application pool (very important), a type of authentification and so forth ??? Thanks.

    Read the article

  • Problem with "moveable-only types" in VC++ 2010

    - by Luc Touraille
    I recently installed Visual Studio 2010 Professional RC to try it out and test the few C++0x features that are implemented in VC++ 2010. I instantiated a std::vector of std::unique_ptr, without any problems. However, when I try to populate it by passing temporaries to push_back, the compiler complains that the copy constructor of unique_ptr is private. I tried inserting an lvalue by moving it, and it works just fine. #include <utility> #include <vector> int main() { typedef std::unique_ptr<int> int_ptr; int_ptr pi(new int(1)); std::vector<int_ptr> vec; vec.push_back(std::move(pi)); // OK vec.push_back(int_ptr(new int(2)); // compiler error } As it turns out, the problem is neither unique_ptr nor vector::push_back but the way VC++ resolves overloads when dealing with rvalues, as demonstrated by the following code: struct MoveOnly { MoveOnly() {} MoveOnly(MoveOnly && other) {} private: MoveOnly(const MoveOnly & other); }; void acceptRValue(MoveOnly && mo) {} int main() { acceptRValue(MoveOnly()); // Compiler error } The compiler complains that the copy constructor is not accessible. If I make it public, the program compiles (even though the copy constructor is not defined). Did I misunderstand something about rvalue references, or is it a (possibly known) bug in VC++ 2010 implementation of this feature?

    Read the article

  • Whats wrong with this video embed code?

    - by jamietelin
    Following embed code is from http://hd.se/landskrona/2010/04/09/kunglig-glans-pa-idrottsgalan/ but it doesn't work in Internet Explorer 8. Firefox no problems. Any recommendations for improvements? Thanks for your time! <object width="480px" height="294px" id="_36313041" data="http://hd.se/static/media/html/flash/video-3/flowplayer.swf" type="application/x-shockwave-flash"> <param name="movie" value="http://hd.se/static/media/html/flash/video-3/flowplayer.swf" /> <param name="allowfullscreen" value="true" /> <param name="allowscriptaccess" value="always" /> <param name="flashvars" value='config={"key":"$3fff7448b28a8cffc85","contextMenu":["hd.se videospelare 1.0"],"plugins":{"rtmp":{"url":"http://hd.se/static/media/html/flash/video-3/flowplayer.rtmp.swf"},"controls":{"height":24,"opacity":1,"all":false,"play":true,"time":true,"scrubber":true,"playlist":false,"mute":true,"volume":true,"fullscreen":true,"backgroundColor":"#222222","backgroundGradient":"none","buttonColor":"#7c7c7c","buttonOverColor":"#36558b","progressColor":"#7c7c7c","bufferColor":"#7c7c7c","timeColor":"#ffffff","durationColor":"#ffffff","timeBgColor":"#222222","scrubberHeightRatio":0.5,"scrubberBarHeightRatio":0.5,"volumeSliderHeightRatio":0.5,"volumeBarHeightRatio":0.5,"autoHide":"fullscreen","hideDelay":1800,"tooltips":{"buttons":true,"play":"Spela","pause":"Paus","next":"Nästa","previous":"Föregående","mute":"Ljud av","unmute":"Ljud på","fullscreen":"Fullskärmsläge","fullscreenExit":"Lämna fullskärmsläge"},"tooltipColor":"#153872","tooltipTextColor":"#ffffff"},"contentIntro":{"url":"http://hd.se/static/media/html/flash/video-3/flowplayer.content.swf","top":0,"width":736,"border":"none","backgroundColor":"#202020","backgroundGradient":"none","borderRadius":"none","opacity":"85pct","display":"none","closeButton":true}},"canvas":{"backgroundColor":"#000000","backgroundGradient":"none"},"play":{"replayLabel":"Spela igen"},"screen":{"bottom":24},"clip":{"scaling":"fit","autoPlay":true},"playlist":[{"provider":"rtmp","netConnectionUrl":"rtmp://fl0.c06062.cdn.qbrick.com/06062","url":"ncode/hdstart","autoPlay":false,"scaling":"fit"},{"url":"http://hd.se/multimedia/archive/00425/_kunligglans_HD_VP6_425359a.flv","scaling":"fit","autoPlay":true},{"provider":"rtmp","netConnectionUrl":"rtmp://fl0.c06062.cdn.qbrick.com/06062","url":"ncode/hdstopp","autoPlay":true,"scaling":"fit"}]}' /> </object>

    Read the article

  • implementing a Intelligent File Transfer Software in java over TCP/IP

    - by whyjava
    Hello I am working on a proposal where we have to implement a software which can move files between one source to destination.The overall goal of this project is to create intelligent file transfer.This software will have three components :- 1) Broker : Broker is the module that communicates with other brokers, monitors files, moves files, retrieves configurations from the Configuration Manager, supplies process information for the monitor, archives files, writes all process data to log files and escalates issues if necessary 2) Configuration Manager :Configuration Manager is a web-based application used to configure and deploy the configuration to all brokers. 3) Monitor : Monitor is a web-based application used to monitor each Broker in the environment. This project has to be built up in java and protocol for file transfer in tcp/ip. Client does not want to use FTP. File Transfer seems very easy, until there are several processes who are waiting to pick the file up automatically. Several problems arise: How can we guarantee the file is received at the destination? If a file isn’t received the first time, we should try it again (even after a restart or power breakdown) ? How does the receiver knows the file that is received is complete? How can we transfer multiple files synchronously? How can we protect the bandwidth, so file transfer isn’t blocking other processes? How does one interoperate between multiple OS platforms? What about authentication? How can we monitor het workflow? Auditing / logging Archiving Can you please provide answer to some of these? Thanks

    Read the article

  • ZeroMQ REQ/REP on ipc:// and concurrency

    - by Metiu
    I implemented a JSON-RPC server using a REQ/REP 0MQ ipc:// socket and I'm experiencing strange behavior which I suspect is due to the fact that the ipc:// underlying unix socket is not a real socket, but rather a single pipe. From the documentation, one has to enforce strict zmq_send()/zmq_recv() alternation, otherwise the out-of-order zmq_send() will return an error. However, I expected the enforcement to be per-client, not per-socket. Of course with a Unix socket there is just one pipeline from multiple clients to the server, so the server won't know who it is talking with. Two clients could zmq_send() simultaneously and the server would see this as an alternation violation. The sequence could be: ClientA: zmq_send() ClientB: zmq_send() : will it block until the other send/receive completes? will it return -1? (I suspect it will with ipc:// due to inherent low-level problems, but with TCP it could distinguish the two clients) ClientA: zmq_recv() ClientB: zmq_recv() so what about tcp:// sockets? Will it work concurrently? Should I use some other locking mechanism to work around this?

    Read the article

  • How much is too much memory allocation in NDK?

    - by Maximus
    The NDK download page notes that, "Typical good candidates for the NDK are self-contained, CPU-intensive operations that don't allocate much memory, such as signal processing, physics simulation, and so on." I came from a C background and was excited to try to use the NDK to operate most of my OpenGL ES functions and any native functions related to physics, animation of vertices, etc... I'm finding that I'm relying quite a bit on Native code and wondering if I may be making some mistakes. I've had no trouble with testing at this point, but I'm curious if I may run into problems in the future. For example, I have game struct defined (somewhat like is seen in the San-Angeles example). I'm loading vertex information for objects dynamically (just what is needed for an active game area) so there's quite a bit of memory allocation happening for vertices, normals, texture coordinates, indices and texture graphic data... just to name the essentials. I'm quite careful about freeing what is allocated between game areas. Would I be safer setting some caps on array sizes or should I charge bravely forward as I'm going now?

    Read the article

  • Fix DB duplicate entries (MySQL bug)

    - by Silence
    I'm using MySQL 4.1. Some tables have duplicates entries that go against the constraints. When I try to group rows, MySQL doesn't recognise the rows as being similar. Example: Table A has a column "Name" with the Unique proprety. The table contains one row with the name 'Hach?' and one row with the same name but a square at the end instead of the '?' (which I can't reproduce in this textfield) A "Group by" on these 2 rows return 2 separate rows This cause several problems including the fact that I can't export and reimport the database. On reimporting an error mentions that a Insert has failed because it violates a constraint. In theory I could try to import, wait for the first error, fix the import script and the original DB, and repeat. In pratice, that would take forever. Is there a way to list all the anomalies or force the database to recheck constraints (and list all the values/rows that go against them) ? I can supply the .MYD file if it can be helpful.

    Read the article

  • Designing model/database for distance between any two locations (that may change)

    - by Yo Ludke
    We should create a web app which has a number of events each with a location (created as user-generated content, so the number of events will be increasingly large). The distance between any events should be available, for example to determine the top 5 closest events and such things. Users may change the locations of events. How should one design the database/model for this (in a scalable way)? I was thinking of doing it with a "distance table" (like so http://www.deutschland-tourist.info/images/entfernungstabelle.gif). Then every time, if a location changes, one row and one column have to be recalculated (this should be done with a delayed job, because it is not important to have the changes instantly). Possible problems in Scaling: Database to large (n² items for n events), too much calculation to be done. For example we should see if this is okay for 10.000 users. If each has created just one event, then this would be 100 million integers... Do you think this would be a good way to do it efficiently? How could one realize such a distance table with an rails model? Is it possible with a SQL databse? Would you start other approaches?

    Read the article

< Previous Page | 533 534 535 536 537 538 539 540 541 542 543 544  | Next Page >