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  • On Memory Allocation and C++

    - by Arpan
    And I quote from MSDN http://msdn.microsoft.com/en-us/library/aa366533(VS.85).aspx: The malloc function has the disadvantage of being run-time dependent. The new operator has the disadvantage of being compiler dependent and language dependent. Now the questions folks: a) What do we mean that malloc is run-time dependent? What kind of dynamic memory allocation functions can be independent of run-time? This statement sounds real strange. b) new is language dependent? Of course it should be right? Are HeapAlloc, LocalAlloc etc language independent? c) From a pure performance perspective are the MSVC provided routines preferable? Arpan

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  • What to return as an iterator when there is no container?

    - by DaClown
    I have an inheritance structure of objects with begin() and end() as pure virtual member functions in the base class. From this objects I'm planning to build a composite structure. This inner objects have std::vector member the begin() and end() get their data from. But in a leaf class there is no vector. Now I try to find a return value for begin() and end() in the leaf classes. What would be a good way to do that? The easiest way would be to have a vector member in the leaf classes with no elements in it to fuel begin() and end(), but this just doesn't feel right.

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  • library interposition with dlsym

    - by ZeeGeek
    I'm writing an interposition library to track the usage of some library functions in libc, such as open(), close(), connect(), etc. It works generally well on most of the applications. However, when I try it with PHP, using PHP's MySQL module in particular, none of the function calls to libc inside this module is been tracked (so no connect(), no socket(), etc.). 'strace' told me that the system calls socket(), connect(), etc., took place. Running 'file' on the module and libmysqlclient.so.16.0.0 said that they are all dynamically linked. So it shouldn't be a problem caused by static linkage. What might be the problem? I'm using Fedora 11 64-bit version. Thank you.

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  • MacOSX: OSAtomic vs OSAtomicBarrier

    - by anon
    For the functions here: #include <libkern/OSAtomic.h> there are OSAtomic and OSAtomicBarrier versions. However, the documentation does not show sample code for: When is it safe to use just OSAtomic, without the OSAtomicBarrier version When is it that OSAtomic would be unsafe, but OSAtomiBarrier would be safe. Can anyone provide explainations + sample codes? [Random ramblings of "your opinion" without actual code is useless. Readers: please down vote such answers; and vigrously upvote answers with actual code.] [C/C++ code preferred; Assembly okay too.]

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  • Does dynamic_cast work inside overloaded operator delete ?

    - by iammilind
    I came across this: struct Base { void* operator new (size_t); void operator delete (void*); virtual ~Base () {} // <--- polymorphic }; struct Derived : Base {}; void Base::operator delete (void *p) { Base *pB = static_cast<Base*>(p); if(dynamic_cast<Derived*>(pB) != 0) { /* ... NOT reaching here ? ... */ } free(p); } Now if we do, Base *p = new Derived; delete p; Surprisingly, the condition inside the Base::delete is not satisfied Am I doing anything wrong ? Or casting from void* looses the information of Derived* ?

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  • How can I (from a script) add something to the zsh command history?

    - by Brandon
    I'd like to be able to look through my command history and know the context from which I issued various commands--in other words, "what directory was I in?" There are various ways I could achieve this, but all of them (that I can think of) would require manipulating the zsh history to add (for instance) a commented line with the result of $(pwd). (I could create functions named cd & pushd & popd etc, or I could use zsh's preexec() function and maybe its periodic() function to add the comment line at most every X seconds, just before I issue a command, or perhaps there's some other way.) The problem is, I don't want to directly manipulate the history file and bypass the shell's history mechanism, but I can't figure out a way (with the fc command, for instance) to add something to the history without actually typing it on the command line. How could I do this?

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  • F# powerpack and distribution

    - by rwallace
    I need arbitrary precision rational numbers, which I'm given to understand are available in the F# powerpack. My question is about the mechanics of distribution; my program needs to be able to compile and run both on Windows/.Net and Linux/Mono at least, since I have potential users on both platforms. As I understand it, the best procedure is: Download the powerpack .zip, not the installer. Copy the DLL into my program directory. Copy the accompanying license file into my program directory, to make sure everything is above board. Declare references and go ahead and use the functions I need. Ship the above files along with my source and binary, and since the DLL uses byte code, it will work fine on any platform. Is this the correct procedure? Am I missing anything?

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  • Can this be done with multiple inhertance?

    - by Milo
    Here is what I would like to do. Say I have Class Widget. I then create Button from Widget. I then create ModifiedWidget which re-implements certain functions of Widget. I then want Button to use ModifiedWidget rather than plain Widget. Is this possible to do some how? Thanks class Button : public Widget; class SuperButton : public Button, public ModifiedWidget; I'm just not sure if that would do what I want it to though.

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  • How to get array keys in Javascript?

    - by DisgruntledGoat
    I have an array created with this code: var widthRange = new Array(); widthRange[46] = { sel:46, min:0, max:52 }; widthRange[66] = { sel:66, min:52, max:70 }; widthRange[90] = { sel:90, min:70, max:94 }; I want to get each of the values 46, 66, 90 in a loop. I tried for (var key in widthRange) but this gives me a whole bunch of extra properties (I assume they are functions on the object). I can't use a regular for loop since the values are not sequential.

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  • troubles with integration on matlab

    - by user648666
    I'd like some help please I really need to solve this problem. Well before anything thank you for your time... My problem: I have a matrix (826x826 double) and I want to integrate this matrix with respect to a vector of (826x1 double) I don't have the functions of any of this. Is there a command or an algorithm to take the integral of a matrix with respect to a vector? Please I really need help, I'm such a newbie at matlab. Sincerely. George

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  • How? Encrypt and Decrypt user membership passwords in ASP.NET

    - by smdrager
    We are creating a new site using ASP.NET membership provider for user registration and log in. Our old system encrypted user passwords so that we could recover them if we needed to. I am having a great deal of trouble figuring out if it is possible to use ASP.NET membership functions to simply encrypt the password when the user registers and then unencrypt it so I can see it. Documentation for this is neigh non-existant. I know how to configure Web.config to have it store passwords as encrypted ala passwordFormat="Hashed" in the provider and assigning a validationKey in the machineKey, however it seems like the password still gets hashed (though perhaps it is just well encrypted). Either way I cannot decifer how the password can be recovered (by us) if neccessary. Thanks!

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  • An easy way to replace fread()'s with reading from a byte array?

    - by Sam Washburn
    I have a piece of code that needs to be run from a restricted environment that doesn't allow stdio (Flash's Alchemy compiler). The code uses standard fopen/fread functions and I need to convert it to read from a char* array. Any ideas on how to best approach this? Does a wrapper exist or some library that would help? Thanks! EDIT: I should also mention that it's reading in structs. Like this: fread(&myStruct, 1, sizeof(myStruct), f);

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  • How should I build a gaming community

    - by Przystojny
    I've been wanting to build my own gaming community site (like http://fragbite.com) for a long time, I have started many times but just quitted after a couple days because it gets very messy I've been palying around with php and mysql off and on for 3 years but i've never gotten in to oop. i have tried but i usually end up with the "old php". I usually build my pages like so that i include a file on top of all pages with neccasary functions, html head etc. And I mix php and html together which I dont mind but if I eventually would get a designer he would not like it i think. I have tried both phpcake and codeigniter and all those popular mvc's but its just to much, like they do all the work. i want to do it myself. but i dont know where to start. What would you do if you were me? Is there maybe some non-oop mvc? (Sorry for my english)

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  • How should I get the value contained in a particular field of a Drupal 7 custom node?

    - by Matt V.
    What is the "proper" way to get the value stored in a particular field within a custom Drupal node? I've created a custom module, with a custom node, with a custom URL field. The following works: $result = db_query("SELECT nid FROM {node} WHERE title = :title AND type = :type", array( ':title' => $title, ':type' => 'custom', ))->fetchField(); $node = node_load($result); $url = $node->url['und']['0']['value']; ...but is there a better way, maybe using the new Field API functions?

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  • Caching result of SELECT statement for reuse in multiple queries

    - by Andrew
    I have a reasonably complex query to extract the Id field of the results I am interested in based on parameters entered by the user. After extracting the relevant Ids I am using the resulting set of Ids several times, in separate queries, to extract the actual output record sets I want (by joining to other tables, using aggregate functions, etc). I would like to avoid running the initial query separately for every set of results I want to return. I imagine my situation is a common pattern so I am interested in what the best approach is. The database is in MS SQL Server and I am using .NET 3.5.

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  • How to encode 'á' to '&#225' with C# ?? (UTF8)

    - by Llorens Marti
    Hi all I'm trying to write an XML file with UTF-8 encode, and the original string can have invalid characters like 'á', so, i need to change these invalid characters to a valid ones. I know that there is an encoding method that take, for example, character 'á' and transform it to group of characters 'á'. I am trying to achive this with C#but i have no succes on it. I am using Encoding.UTF8 functions but i only end with the sema character (i.e: á) or a '?' character. So, do you know with is the correct way to achive this character change with C# ?? Thanks for your time and help :) LLORENS

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  • Is there is something like stored procedures in NOSQL databases?

    - by Amr ElGarhy
    I am new to NOSQL world and still comparing between nosql and sql databases, I Just tried making few samples using mongodb. I am asking about stored procedures when we send few parameters to one stored procedure and this procedure execute number of other stored procedures in the database, will get data from stored procedures and send data to others. In other words, will make the logic happen on the database side using sequence of functions and stored procedures. Is that behavior or something the same already exist on NOSQL databases, or its completely different and i am thinking in the wrong way?

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  • Wordpress page linking

    - by danixd
    I am trying to implement WordPress into quite a large site with a complex page structure and struggling to get normal pages to work (not created through the admin) The pages are created, but when I link to them, nothing happens... The desired url - www.website.com/dir1/dir2/dir3/page.php The actual url- www.website.com/wp-content/themes/themename/dir1/dir2/dir3/page.php The problem with linking to the latter is that it breaks the WordPress functions I don't want to have to give every page a template, then add it through the admin, it is too much work. I only need 2 pages to contain dynamic content. Am I being silly? I am really confused.

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  • Does C++ have a static polymorphism implementation of interface that does not use vtable?

    - by gilbertc
    Does C++ have a proper implementation of interface that does not use vtable? for example class BaseInterface{ public: virtual void func() const = 0; } class BaseInterfaceImpl:public BaseInterface{ public: void func(){ std::cout<<"called."<<endl; } } BaseInterface* obj = new BaseInterfaceImpl(); obj->func(); the call to func at the last line goes to vtable to find the func ptr of BaseInterfaceImpl::func, but is there any C++ way to do that directly as the BaseInterfaceImpl is not subclassed from any other class besides the pure interface class BaseInterface? Thanks. Gil.

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  • How often do you implement the big three?

    - by Neil Butterworth
    I was just musing about the number of questions here that either are about the "big three" (copy constructor, assignment operator and destructor) or about problems caused by them not being implemented correctly, when it occurred to me that I could not remember the last time I had implemented them myself. A swift grep on my two most active projects indicate that I implement all three in only one class out of about 150. That's not to say I don't implement/declare one or more of them - obviously base classes need a virtual destructor, and a large number of my classes forbid copying using the private copy ctor & assignment op idiom. But fully implemented, there is this single lonely class, which does some reference counting. So I was wondering am I unusual in this? How often do you implement all three of these functions? Is there any pattern to the classes where you do implement them?

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  • Is it possible to configure Apache to host both an ASP.NET Web Service and a PHP Web site?

    - by Eduardo León
    Noob question (because I'm a noob when it comes to Web development). I'm not sure whether I should ask it here or at ServerFault. I am developing an ASP.NET Web Service and a PHP Web site consuming the Web Service. They are meant to be run on different machines. However, only for development purposes, I need to run both on my machine. I cannot use virtual machines. I would like to know if it is possible to configure IIS Apache to host both my Web Service and my Web site? Or, do I need to host the PHP site using Apache? I am using IIS 7.5 Apache HTTP Server 2.2 (NOTE: I have nothing against Apache. In fact, so far I like it more than IIS, however, I would rather not have two Web server applications installed in the same machine.) PHP 5.3.4 .NET Framework 2.0 3.0 or 3.5 (whichever comes with Visual Studio 2008) mod_aspdotnet for Apache 2.2

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  • How to explicitly terminate http connection from server with no response header

    - by Gagandip
    I am developing a server simulator for one of my client application. I am using GlassFish server. I have to simulate a http connection terminate condition in my server application. Is there a way by which I can explicitly terminate a connection from server side such that client does not receive any response header. Currently I have tried many options like closing the response outputStream. But in every case a http 200 OK message is delivered to the client application. I would like to consume the http-request and do not want to return anything to the client. I am using a simple conrtroller servlet and had overridden doGet() and doPost() functions.

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  • How can I delete video stored in the photo library ?

    - by srikanth rongali
    I have saved video in to the photo library. -(void)exportVideo:(id)sender { NSString *path = [DOCUMENTS_FOLDER stringByAppendingString:@"/air.mp4"]; NSLog(@"Path:%@", path); NSLog(@"Export Button CLicked"); UISaveVideoAtPathToSavedPhotosAlbum(path, self, @selector(video:didFinishSavingWithError: contextInfo:), nil); } - (void)video:(NSString *)videoPath didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo { NSLog(@"Finished saving video with error: %@", error); } Now I need to delete the video i have stored programmatically. How can I delete the video ? Are there any functions for it? Thank You.

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  • WSAT Security tab error for Custom Role provider

    - by shesb
    I have created custome Membership Role and Profile provider using INGRES db. Now I can see my IngresMembership and IngresRole provider in the Provider tab(Select a different provider for each feature (advanced) ) of WSAT but when I clik on security tab I get this error: "There is a problem with your selected data store. This can be caused by an invalid server name or credentials, or by insufficient permission. It can also be caused by the role manager feature not being enabled. Click the button below to be redirected to a page where you can choose a new data store. The following message may help in diagnosing the problem: Object reference not set to an instance of an object." What am I missing? Do I need to add code for all override methods for Role provider? I have just written code for the Initialize and GetRolesForUser functions. Thanks

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  • jQuery plugin call internal function

    - by pbcoder
    I want to call removeSomething() (see in line 9) internally: JS-Code is: (function($){ $.fn.extend({ Engine: function(options) { var defaults = { ... }; var options = $.extend(defaults, options); removeSomething(); //----------------------------------------------------------------------- //Public Functions ------------------------------------------------------ //----------------------------------------------------------------------- this.removeSomething = function() { ... }; } }); })(jQuery); But if I call removeSomething console outputs that removeSomething is not a function, how do I have to call this function? The function should be available internally and externally. Thanks for help!

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