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  • Socket isn't listed by netstat unless using certain ports

    - by illuzive
    I'm a computer science student with a few years of programming experience. Yesterday, while working on a project (Mac OS X, BSD sockets) at school, I encountered a strange problem. I was adding several modules to a very basic "server" (mostly a bunch of functions to set up and manage an UDP socket on a certain port). While doing this, I started the server from time to time in order to see that everything worked like it should. I've been using port 32000 during the development of the server. When I start the server and run netstat, the socket is listed as expected. > netstat -p UDP | grep 32000 udp46 0 0 *.32000 *.* However, when I run the server on other ports (random (10000 - 50000)), it's not listed by netstat. My thought was that I had somehow hard coded the port somewhere in the code, but that's not the case. The thing is - I can connect to the socket on any of the tested ports, and it reads data sent to it without any problem at all. It just doesn't get listed by netstat. What I wonder, is if anyone of you have any idea of why this happens? Note: Although this is a project at school, it's not homework. This is just something I want to understand for my own benefit.

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  • Recursion in assembly?

    - by Davis
    I'm trying to get a better grasp of assembly, and I am a little confused about how to recursively call functions when I have to deal with registers, popping/pushing, etc. I am embedding x86 assembly in C++. Here I am trying to make a method which given an array of integers will build a linked list containing these integers in the order they appear in the array. I am doing this by calling a recursive function: insertElem (struct elem *head, struct elem *newElem, int data) -head: head of the list -data: the number that will be inserted at the end of a list -newElem: points to the location in memory where I will store the new element (data field) My problem is that I keep overwriting the registers instead of a typical linked list. For example, if I give it an array {2,3,1,8,3,9} my linked-list will return the first element (head) and only the last element, because the elements keep overwriting each other after head is no longer null. So here my linked list looks something like: 2--9 instead of 2--3--1--8--3--9 I feel like I don't have a grasp on how to organize and handle the registers. newElem is in EBX and just keeps getting rewritten. Thanks in advance!

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  • Help with an RSS Feed

    - by Pete Herbert Penito
    Hi Everyone! I've spent ages on this, all I'm trying to do is extract the "title" contents from an rss feed, everything else can be ignored. I've looked into simplepie, magpie and all that stuff, but I feel its kind of overkill for what I need to do. I realise there are google gadgets that are made that can do this, but I didn't want all the google logo stuff, and I wanted to personally make this. theres a whole bunch of unneeded tags thats coming in from the rss feed all I need is the title tag, it looks like this <title> My Title 3.0 </title> My server has PHP 5+ so I know I can use some of these simple xml functions which look promising. so far I've got <?php $blogfeed = file_get_contents("http://myblog.blogspot.com/feeds/posts/default?alt=rss"); echo $blogfeed; ?> And it gives me all the data, I was thinking of running through it with strpos and searching for <title> but is there any easier way to do this?? Thanks alot!

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  • Clarification of atomic memory access for different OSs

    - by murrekatt
    I'm currently porting a Windows C++ library to MacOS as a hobby project as a learning experience. I stumbled across some code using the Win Interlocked* functions and thus I've been trying to read up on the subject in general. Reading related questions here in SO, I understand there are different ways to do these operations depending on the OS. Interlocked* in Windows, OSAtomic* in MacOS and I also found that compilers have builtin (intrinsic) operations for this. After reading gcc builtin atomic memory access, I'm left wondering what is the difference between intrinsic and the OSAtomic* or Interlocked* ones? I mean, can I not choose between OSAtomic* or gcc builtin if I'm on MacOS when I use gcc? The same if I'd be on Windows using gcc. I also read that on Windows Interlocked* come as both inline and intrinsic versions. What to consider when choosing between intrinsic or inline? In general, are there multiple options on OSs what to use? Or is this again "it depends"? If so, what does it depend on? Thanks!

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  • Where to store site settings: DB? XML? CONFIG? CLASS FILES?

    - by Emin
    I am re-building a news portal of which already have a large number of visits every day. One of the major concerns when re-building this site was to maximize performance and speed. Having said this, we have done many things from caching, to all sort of other measures to ensure speed. Now towards the end of the project, I am having a dilemma of where to store my site settings that would least affect performance. The site settings will include things such as: Domain, DefaultImgPath, Google Analytics code, default emails of editors as well as more dynamic design/display feature settings such as the background color of specific DIVs and default color for links etc.. As far as I know, I have 4 choices in storing all these info. Database: Storing general settings in the DB and caching them may be a solution however, I want to limit the access to the database for only necessary and essential functions of the project which generally are insert/update/delete news items, author articles etc.. XML: I can store these settings in an XML file but I have not done this sort of thing before so I don't know what kind of problems -if any- I might face in the future. CONFIG: I can also store these settings in web.config CLASS FILE: I can hard code all these settings in a SiteSettings class, but since the site admin himself will be able to edit these settings, It may not be the best solution. Currently, I am more close to choosing web.config but letting people fiddle with it too often is something I do not want. E.g. if somehow, I miss out a validation for something and it breaks the web.config, the whole site will go down. My concern basically is that, I cannot forsee any possible consequences of using any of the methods above (or is there any other?), I was hoping to get this question over to more experienced people out here who hopefully help make my decision.

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  • Improving File Read Performance (single file, C++, Windows)

    - by david
    I have large (hundreds of MB or more) files that I need to read blocks from using C++ on Windows. Currently the relevant functions are: errorType LargeFile::read( void* data_out, __int64 start_position, __int64 size_bytes ) const { if( !m_open ) { // return error } else { seekPosition( start_position ); DWORD bytes_read; BOOL result = ReadFile( m_file, data_out, DWORD( size_bytes ), &bytes_read, NULL ); if( size_bytes != bytes_read || result != TRUE ) { // return error } } // return no error } void LargeFile::seekPosition( __int64 position ) const { LARGE_INTEGER target; target.QuadPart = LONGLONG( position ); SetFilePointerEx( m_file, target, NULL, FILE_BEGIN ); } The performance of the above does not seem to be very good. Reads are on 4K blocks of the file. Some reads are coherent, most are not. A couple questions: Is there a good way to profile the reads? What things might improve the performance? For example, would sector-aligning the data be useful? I'm relatively new to file i/o optimization, so suggestions or pointers to articles/tutorials would be helpful.

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  • Boost multi_index_container crash in release mode

    - by Zan Lynx
    I have a program that I just changed to using a boost::multi_index_container collection. After I did that and tested my code in debug mode, I was feeling pretty good about myself. However, then I compiled a release build with NDEBUG set, and the code crashed. Not immediately, but sometimes in single-threaded tests and often in multi-threaded tests. The segmentation faults happen deep inside boost insert and rotate functions related to the index updates and they are happening because a node has NULL left and right pointers. My code looks a bit like this: struct Implementation { typedef std::pair<uint32_t, uint32_t> update_pair_type; struct watch {}; struct update {}; typedef boost::multi_index_container< update_pair_type, boost::multi_index::indexed_by< boost::multi_index::ordered_unique< boost::multi_index::tag<watch>, boost::multi_index::member<update_pair_type, uint32_t, &update_pair_type::first> >, boost::multi_index::ordered_non_unique< boost::multi_index::tag<update>, boost::multi_index::member<update_pair_type, uint32_t, &update_pair_type::second> > > > update_map_type; typedef std::vector< update_pair_type > update_list_type; update_map_type update_map; update_map_type::iterator update_hint; void register_update(uint32_t watch, uint32_t update); void do_updates(uint32_t start, uint32_t end); }; void Implementation::register_update(uint32_t watch, uint32_t update) { update_pair_type new_pair( watch_offset, update_offset ); update_hint = update_map.insert(update_hint, new_pair); if( update_hint->second != update_offset ) { bool replaced _unused_ = update_map.replace(update_hint, new_pair); assert(replaced); } }

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  • File streaming in PHP - How to replicate this C#.net code in PHP?

    - by openid_kenja
    I'm writing an interface to a web service where we need to upload configuration files. The documentation only provides a sample in C#.net which I am not familiar with. I'm trying to implement this in PHP. Can someone familiar with both languages point me in the right direction? I can figure out all the basics, but I'm trying to figure out suitable PHP replacements for the FileStream, ReadBytes, and UploadDataFile functions. I believe that the RecService object contains the URL for the web service. Thanks for your help! private void UploadFiles() { clientAlias = “<yourClientAlias>”; string filePath = “<pathToYourDataFiles>”; string[] fileList = {"Config.txt", "ProductDetails.txt", "BrandNames.txt", "CategoryNames.txt", "ProductsSoldOut.txt", "Sales.txt"}; RecommendClient RecService = new RecommendClient(); for (int i = 0; i < fileList.Length; i++) { bool lastFile = (i == fileList.Length - 1); //start generator after last file try { string fileName = filePath + fileList[i]; if (!File.Exists(fileName)) continue; // file not found } // set up a file stream and binary reader for the selected file and convert to byte array FileStream fStream = new FileStream(fileName, FileMode.Open, FileAccess.Read); BinaryReader br = new BinaryReader(fStream); byte[] data = br.ReadBytes((int)numBytes); br.Close(); // pass byte array to the web service string result = RecService.UploadDataFile(clientAlias, fileList[i], data, lastFile); fStream.Close(); fStream.Dispose(); } catch (Exception ex) { // log an error message } } }

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  • How to encapsulate a WinAPI application into a C++ class

    - by Semen Semenych
    There is a simple WinAPI application. All it does currently is this: register a window class register a tray icon with a menu create a value in the registry in order to autostart and finally, it checks if it's unique using a mutex As I'm used to writing code mainly in C++, and no MFC is allowed, I'm forced to encapsulate this into C++ classes somehow. So far I've come up with such a design: there is a class that represents the application it keeps all the wndclass, hinstance, etc variables, where the hinstance is passed as a constructor parameter as well as the icmdshow and others (see WinMain prototype) it has functions for registering the window class, tray icon, reigstry information it encapsulates the message loop in a function In WinMain, the following is done: Application app(hInstance, szCmdLIne, iCmdShow); return app.exec(); and the constructor does the following: registerClass(); registerTray(); registerAutostart(); So far so good. Now the question is : how do I create the window procedure (must be static, as it's a c-style pointer to a function) AND keep track of what the application object is, that is, keep a pointer to an Application around. The main question is : is this how it's usually done? Am I complicating things too much? Is it fine to pass hInstance as a parameter to the Application constructor? And where's the WndProc? Maybe WndProc should be outside of class and the Application pointer be global? Then WndProc invokes Application methods in response to various events.

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  • Attach an entity that is not new, perhaps having been loaded from another DataContext. LINQ to SQL -

    - by soldieraman
    Alright How I got this error I got one application sitting on a server 2 users accessing this application - doing some bulk data processing . eg. entering values and then the application is working with another system to extract values for them and then saving. I can't recreate the error The error logs show: The error happend at the same time in both the application Both happend on a Attach/Submit (but two different functions) There is no way they are using the same DataContext object as I save the DataContext in the HttpContext.Items My hunch / guess is: One datacontext was not refreshed i.e. the an object was created for the same item twice as it was new in both the forms. eg. Customer Number - a customer was created (as one couldn't be found) by one datacontext - the other one couldn't find it either (i am using compiled queries to find it in the datacontext) so it created another object and on attaching failed. The HttpContext.Items lost its value somehow (i am using a virtual pc as server - maybe something went wrong there) I am going more of the second as I can't recreate the error - but it just might be a timing (for attach/save) thing - also the error makes me think of the 2nd too.

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  • Coupling an MFC CListCtrl and CTreeCtrl to get a view of the whole tree, not just one node at a time

    - by omatai
    Consider Windows Explorer (or regedit or similar). To the left side, there is a tree view, and to the right, a list view. In all cases I know of, the contents of the right view reflect the attributes of the selected node from the left pane. This is all well and good... but just not what I want. The nodes of the tree I want to display have a very few attributes (2-3) associated with each node - a reasonable amount to display horizontally as a row in a table. Rather than waste all that list view space on a single node with very few properties, I would like to have my list view display a table of the whole tree's properties (as the part of the tree currently expanded). So the nth line in the left view (tree) will correspond directly to the nth line in the right view (list/table), and I will get a decent overview of the properties of my tree. Does anyone know of code that does this? I am guessing that slaving a CListCtrl to a CTreeCtrl would be the way to go, and somehow overriding the vertical scrolling functions so that they are locked together. I'm just not sure that it is possible to lock the scrolls together like this... among other things! All advice gratefully welcomed :-)

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  • Program structure in long running data processing python script

    - by fmark
    For my current job I am writing some long-running (think hours to days) scripts that do CPU intensive data-processing. The program flow is very simple - it proceeds into the main loop, completes the main loop, saves output and terminates: The basic structure of my programs tends to be like so: <import statements> <constant declarations> <misc function declarations> def main(): for blah in blahs(): <lots of local variables> <lots of tightly coupled computation> for something in somethings(): <lots more local variables> <lots more computation> <etc., etc.> <save results> if __name__ == "__main__": main() This gets unmanageable quickly, so I want to refactor it into something more manageable. I want to make this more maintainable, without sacrificing execution speed. Each chuck of code relies on a large number of variables however, so refactoring parts of the computation out to functions would make parameters list grow out of hand very quickly. Should I put this sort of code into a python class, and change the local variables into class variables? It doesn't make a great deal of sense tp me conceptually to turn the program into a class, as the class would never be reused, and only one instance would ever be created per instance. What is the best practice structure for this kind of program? I am using python but the question is relatively language-agnostic, assuming a modern object-oriented language features.

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  • Magento: Attribute always returns default value in catalog view, works fine in product view

    - by colinodell
    I've created a new Yes/No attribute for products. I've extended the Product model to do some custom logic and the custom functions are working everywhere. When I initially tried getting the custom attribute value, I ran into some issue. Magento wasn't loading it for me, so calls to $product-getMyAttributeName() did nothing. In the product views, I got it working with this additional function: public function getAttrVal($attr_name) { return $this->getResource()->getAttribute($attr_name)->getFrontend()->getValue($this); } So that worked great when viewing a product on the frontend. It would fetch the assigned value if set, or the default if not. When I view any Category (grid of all products in that category), the same exact code is being executed. But my getAttrVal() function always returns the default value, even if I've explicitly set this value for my product. I can't, for the life of me, figure out why the attribute loads correctly in the Product view but the Category view always grabs the default value, despite running the same exact code. Any thoughts?

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  • How to return a record from function, executed by INSERT/UPDATE rule (trigger)?

    - by seas
    Do the following scheme for my database: create sequence data_sequence; create table data_table { id integer primary key; field varchar(100); }; create view data_view as select id, field from data_table; create function data_insert(_new data_view) returns data_view as $$declare _id integer; _result data_view%rowtype; begin _id := nextval('data_sequence'); insert into data_table(id, field) values(_id, _new.field); select * into _result from data_view where id = _id; return _result; end; $$ language plpgsql; create rule insert as on insert to data_view do instead select data_insert(new); Then type in psql: insert into data_view(field) values('abc'); Would like to see something like: id | field ----+--------- 1 | abc Instead see: data_insert ------------- (1, "abc") Is it possible to fix this somehow? Thanks for any ideas. Ultimate idea is to use this in other functions, so that I could obtain id of just inserted record without selecting for it from scratch. Something like: insert into data_view(field) values('abc') returning id into my_variable would be nice but doesn't work with error: ERROR: cannot perform INSERT RETURNING on relation "data_view" HINT: You need an unconditional ON INSERT DO INSTEAD rule with a RETURNING clause. I don't really understand that HINT. I use PostgreSQL 8.4.

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  • Finding cause of memory leaks in large PHP stacks

    - by Mike B
    I have CLI script that runs over several thousand iterations between runs and it appears to have a memory leak. I'm using a tweaked version of Zend Framework with Smarty for view templating and each iteration uses several MB worth of code. The first run immediately uses nearly 8MB of memory (which is fine) but every following run adds about 80kb. My main loop looks like this (very simplified) $users = UsersModel::getUsers(); foreach($users as $user) { $obj = new doSomethingAwesome(); $obj->run($user); $obj = null; unset($obj); } The point is that everything in scope should be unset and the memory freed. My understanding is that PHP runs through its garbage collection process at it's own desire but it does so at the end of functions/methods/scripts. So something must be leaking memory inside doSomethingAwesome() but as I said it is a huge stack of code. Ideally, I would love to find some sort of tool that displayed all my variables no matter the scope at some point during execution. Some sort of symbol-table viewer for php. Does anything like that or any other tools that could help nail down memory leaks in php exist?

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  • Session variables not getting set but only in Internet Explorer and not on all machines

    - by gaoshan88
    Logging into a site I'm working on functions as expected on my local machine but fails on the remote server but ONLY in Internet Explorer. The kicker is that it works in IE locally, just not on the remote machine. What in the world could cause this? I have stepped through the code on the remote machine and can see the entered login values being checked in the database, they are found and then a login function is called. This sets two $_SESSION variables and redirects to the main admin page. However, in IE only (and not when run on local machine... this is key) the $_SESSION variables are not present by the time you get to the main admin page. var_dump($_SESSION) gives me what I expect on every browser when I am running this in my local environment and in every browser except IE 6, 7 and 8 when run on the remote server (where I get a null value as if nothing has been set for $_SESSION). This really has me stumped so any advice is appreciated. For an example... in IE, run locally, var_dump gives me: array 'Username' => string 'theusername' length=11 'UserID' => string 'somevalue' length=9 Run on the remote server (IE only... works fine in other browsers) var_dump gives me: array(0){} Code: $User = GetUser($Username, $Password); if ($User->UserID <> "") { // this works so we call Login()... Login($User); // this also works and gives expected results. on to redirect... header("Location: index.php"); // a var_dump at index.php shows that there is no session data at all in IE, remotely. } else { header("Location: login.php"); } function Login($data) { $_SESSION['Username'] = $data->Username; $_SESSION['UserID'] = $data->UserID; // a var dump here gives the expected data in every browser }

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  • Am I understanding premature optimization correctly?

    - by Ed Mazur
    I've been struggling with an application I'm writing and I think I'm beginning to see that my problem is premature optimization. The perfectionist side of me wants to make everything optimal and perfect the first time through, but I'm finding this is complicating the design quite a bit. Instead of writing small, testable functions that do one simple thing well, I'm leaning towards cramming in as much functionality as possible in order to be more efficient. For example, I'm avoiding multiple trips to the database for the same piece of information at the cost of my code becoming more complex. One part of me wants to just not worry about redundant database calls. It would make it easier to write correct code and the amount of data being fetched is small anyway. The other part of me feels very dirty and unclean doing this. :-) I'm leaning towards just going to the database multiple times, which I think is the right move here. It's more important that I finish the project and I feel like I'm getting hung up because of optimizations like this. My question is: is this the right strategy to be using when avoiding premature optimization?

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  • RTTI Dynamic array TValue Delphi 2010

    - by user558126
    Hello I have a question. I am a newbie with Run Time Type Information from Delphi 2010. I need to set length to a dynamic array into a TValue. You can see the code. Type TMyArray = array of integer; TMyClass = class publihed function Do:TMyArray; end; function TMyClass.Do:TMyArray; begin SetLength(Result,5); for i:=0 to 4 Result[i]=3; end; ....... ....... ...... y:TValue; Param:array of TValue; ......... y=Methods[i].Invoke(Obj,Param);//delphi give me a DynArray type kind, is working, Param works to any functions. if Method[i].ReturnType.TypeKind = tkDynArray then//is working... begin I want to set length for y to 10000//i don't know how to write. end; I don't like Generics Collections.

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  • php and mysql site design question

    - by Jacksta
    I am trying to build a website with mysql and php. This is the first site I have attempted so I want to write a little plan and get some feedback. The site allows users to add some text in a text field as a “comment”. Once the comment has been entered into the site it is added to the database where it can be voted for by other users. When a new comment has been added to the database it needs to create a new page, e.g. www.xxxxx.com/commentname or www.xxxxxx.com/?id=99981. There will be a list of "Comments" in the database along with the number of votes for each comment. The home page will have two functions. 1) Allow users to add a "comment" 2) Display two tables, each with 20 rows containing most "popular comments" and "recent comments" Each comment will generate its one page where the comment will be displayed. Here users can read the comment and Vote for the comment if they wish. Please help me out by explaining how to do the following. -Generate a new page whenever a comment is added to the database -Add a vote to the vote count in the comment database. -Display the top 20 most popular comments as per number of votes.

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  • Event not triggering

    - by the Hampster
    I have no idea where to start on this one. I have a that does not appear until a button is clicked. This function call works: onclick="highlight('mod_sup_div', true);" function highlight(aDiv,show) { if (show) { Effect.Appear('Overlay',{duration: 0.5, to: .80}); Effect.Appear(aDiv,{duration: 0.5}) } else { Effect.Fade('Overlay',{duration: 0.5, to: .80}); Effect.Fade(aDiv,{duration: 0.5}) } } In the <div> I have a button to close the window. <p class="closer"><span onclick="highlight('mod_sup_div',false)">X</span></p> This does not work. The function is not even called, as I made a alert() the first line of the function at it does nothing. What is odd, is that onclick="Effect.Fade(aDiv,{duration: 0.5})" does work. Other simple javascript functions in the onclick="" work, except for the function call. Any help as to why this is happening would be very appreciated. Thanks, Dave

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  • How to modify Keyboard interrupt (under Windows XP) from a C++ Program ?

    - by rockr90
    Hi everyone ! We have been given a little project (As part of my OS course) to make a Windows program that modifies keyboard input, so that it transforms any lowercase character entered into an uppercase one (without using caps-lock) ! so when you type on the keyboard you'll see what you're typing transformed into uppercase ! I have done this quite easily using Turbo C by calling geninterrupt() and using variables _AH, _AL, i had to read a character using: _AH = 0x07; // Reading a character without echo geninterrupt(0x21); // Dos interrupt Then to transform it into an Upercase letter i have to mask the 5th bit by using: _AL = _AL & 0xDF; // Masking the entered character with 11011111 and then i will display the character using any output routine. Now, this solution will only work under old C DOS compilers. But what we intend to do is to make a close or similar solution to this by using any modern C/C++ compiler under Windows XP ! What i have first thought of is modifying the Keyboard ISR so that it masks the fifth bit of any entered character to turn it uppercase ! But i do not know how exactly to do this. Second, I wanted to create a Win32 console program to either do the same solution (but to no avail) or make a windows-compatible solution, still i do not know which functions to use ! Third I thought to make a windows program that modifies the ISR directly to suit my needs ! and i'm still looking for how to do this ! So please, If you could help me out on this, I would greatly appreciate it ! Thank you in advance ! (I'm using Windows XP on intel X86 with mingw-GCC compiler.)

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  • Implementation problem. Htaccess in php

    - by Irwan
    I have a problem to fix the URL on my website at http://www.abelputra.com I need a solution: I want to change www.abelputra.com/software.php into www.abelputra.com/software I have read a tutorial like this: For .htaccess: RewriteEngine On RewriteRule ^ ([a-zA-Z0-9_-] +) $ index.php? Key = $ 1 RewriteRule ^ ([a-zA-Z0-9_-]+)/$ index.php? Key = $ 1 Then in php: index.php --- $Key=$ _GET ['key']; if ($key == 'home') { include ('index.php'); // Home page } else if ($ key == 'software') { include ('software.php'); // } else if ($ key == 'webdesign') { include ('webdesign.php'); // } The problem is: When I implemented the menu software.php index.php to call the page: www.abelputra.com/index.php?key=software what happens is the page that is shown is two pages later software.php index.php page underneath. Is it because calling functions "include ()"? index.php structures: Header Content - contains the opening words Footer software.php structure: Header Content - contains an explanation of my software Footer Sorry my english bad. im from Indonesia. Please solution .. thanks

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  • virtual methods and template classes

    - by soxs060389
    Hi I got over a problem, I think a very specific one. I've got 2 classes, a B aseclass and a D erived class (from B aseclass). B is a template class ( or class template) and has a pure virtual method virutal void work(const T &dummy) = 0; The D erived class is supposed to reimplement this, but as D is Derived from B rather than D being another template class, the compiler spits at me that virtual functions and templates don't work at once. Any ideas how to acomplish what I want? I am thankfull for any thoughts and Ideas, especially if you allready worked out that problem this class is fixed aka AS IS, I can not edit this without breaking existing code base template <typename T> class B { public: ... virtual void work(const T &dummy) = 0; .. }; take int* as an example class D : public B<int*>{ ... virtual void work(const int* &dummy){ /* put work code here */ } .. }; Edit: The compiler tells me, that void B<T>::work(const T&) [with T = int*] is pure virtual within D

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  • Using function arguments to dynamically generate a query

    - by Varun
    I am working on an issue management system, developed in PHP/MySQL. It requires search functionality, where the user will mention the search parameters and based on these parameters the system will return the result set. To solve this I am trying to write a function and all the user selected parameters are passed as arguments. Based on the arguments I will dynamically generate the query. Sample Query: select * from tickets inner join ticket_assigned_to on tickets.id=ticket_assigned_to.ticket_id where tickets.project_id= in ('') and tickets.status in ('') and ticket_assigned_to.user_id in ('') and tickets.reporter_user_id='' and tickets.operator_user_id in ('') and tickets.due_date between '' and '' and tickets.ts_created between '' and ''; I also need to handle cases where the arguments can be ORed or ANDed in the query. For example: select * from tickets inner join ticket_assigned_to on tickets.id=ticket_assigned_to.ticket_id where tickets.project_id= in ('') and tickets.status in ('') or tickets.due_date = '' or tickets.ts_created between '' and ''; I am also planning to use the same function at other places in the project also. Like to display all the tickets of a user or all tickets created between given dates and so on... How to handle this situation? Should I go with a single function which handles all this or numerous small functions? Need guidance here.

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  • Extremely CPU Intensive Alarm Clock

    - by SoulBeaver
    For some reason my program, a console alarm clock I made for laughs and practice, is extremely CPU intensive. It consumes about 2mB RAM, which is already quite a bit for such a small program, but it devastates my CPU with over 50% resources at times. Most of the time my program is doing nothing except counting down the seconds, so I guess this part of my program is the one that's causing so much strain on my CPU, though I don't know why. If it is so, could you please recommend a way of making it less, or perhaps a library to use instead if the problem can't be easily solved? /* The wait function waits exactly one second before returning to the * * called function. */ void wait( const int &seconds ) { clock_t endwait; // Type needed to compare with clock() endwait = clock() + ( seconds * CLOCKS_PER_SEC ); while( clock() < endwait ) {} // Nothing need be done here. } In case anybody browses CPlusPlus.com, this is a genuine copy/paste of the clock() function they have written as an example for clock(). Much why the comment //Nothing need be done here is so lackluster. I'm not entirely sure what exactly clock() does yet. The rest of the program calls two other functions that only activate every sixty seconds, otherwise returning to the caller and counting down another second, so I don't think that's too CPU intensive- though I wouldn't know, this is my first attempt at optimizing code. The first function is a console clear using system("cls") which, I know, is really, really slow and not a good idea. I will be changing that post-haste, but, since it only activates every 60 seconds and there is a noticeable lag-spike, I know this isn't the problem most of the time. The second function re-writes the content of the screen with the updated remaining time also only every sixty seconds. I will edit in the function that calls wait, clearScreen and display if it's clear that this function is not the problem. I already tried to reference most variables so they are not copied, as well as avoid endl as I heard that it's a little slow compared to \n.

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