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• Get the src part of a string [duplicate]

  - by Kay Lakeman

  This question already has an answer here: Grabbing the href attribute of an A element 7 answers First post ever here, and i really hope you can help. I use a database where a large piece of html is stored, now i just need the src part of the image tag. I already found a thread, but i just doesn't do the trick. My code: Original string: <p><img alt=\"\" src=\"http://domain.nl/cms/ckeditor/filemanager/userfiles/background.png\" style=\"width: 80px; height: 160px;\" /></p> How i start: $image = strip_tags($row['information'], '<img>'); echo stripslashes($image); This returns: <img alt="" src="http://domain.nl/cms/ckeditor/filemanager/userfiles/background.png" style="width: 80px; height: 160px;" /> Next step: extract the src part: preg_match('/< *img[^>]*src *= *["\']?([^"\']*)/i', $image, $matches); echo $matches ; This last echo returns: Array What is going wrong? Thanks in advance for your anwser.

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• Should I be using Expression Blend to design really dynamic UIs?

  - by Robert Rossney

  My company's product is, at its core, a framework for developing metadata-driven UIs. I don't know how to characterize it less succinctly than that, and hope I won't need to for purposes of this question, but we'll see. I've been trying to come up to speed on WPF, and have been building UI prototypes here and there, and recently I decided to see if I could use Expression Blend to help with the design of these UIs. And I'm pretty mystified at this point. It appears to me as though Expresssion Blend is designed with the expectation that you already know all of the objects that are going to be present in the UI at design time. But our program generates these object dynamically at runtime. For instance, a data row might be presented in a horizontal StackPanel containing alternating TextBlocks (for captions) and TextBoxes (for data fields). The number of these objects depends on metadata about the number of columns in the data row. I can, pretty readily, write code that runs through a metadata record and populates a StackPanel dynamically, setting up the binding of all of the controls to properties in either the data or metadata. (A TextBox's Width might be bound to metadata, while its Text is bound to data.) But I can't even begin to figure out how to do something like this in Expression Blend. I can manually create all these controls, so that I have a set of controls that I can apply styles to and work out the visual design of the app, but it's really a pain to do this. I can write code that goes through my data model and emits XAML for all these controls, I suppose, and then copy and paste it. But I'm going to feel really stupid if it turns out there a way to do this sort of thing in Expression Blend and I've dropped back and punted because I'm too dim to figure out the right way to think of it. Is this enough information for someone to try formulating an answer?

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• GUID or int entity key with SQL Compact/EF4?

  - by David Veeneman

  This is a follow-up to an earlier question I posted on EF4 entity keys with SQL Compact. SQL Compact doesn't allow server-generated identity keys, so I am left with creating my own keys as objects are added to the ObjectContext. My first choice would be an integer key, and the previous answer linked to a blog post that shows an extension method that uses the Max operator with a selector expression to find the next available key: public static TResult NextId<TSource, TResult>(this ObjectSet<TSource> table, Expression<Func<TSource, TResult>> selector) where TSource : class { TResult lastId = table.Any() ? table.Max(selector) : default(TResult); if (lastId is int) { lastId = (TResult)(object)(((int)(object)lastId) + 1); } return lastId; } Here's my take on the extension method: It will work fine if the ObjectContext that I am working with has an unfiltered entity set. In that case, the ObjectContext will contain all rows from the data table, and I will get an accurate result. But if the entity set is the result of a query filter, the method will return the last entity key in the filtered entity set, which will not necessarily be the last key in the data table. So I think the extension method won't really work. At this point, the obvious solution seems to be to simply use a GUID as the entity key. That way, I only need to call Guid.NewGuid() method to set the ID property before I add a new entity to my ObjectContext. Here is my question: Is there a simple way of getting the last primary key in the data store from EF4 (without having to create a second ObjectContext for that purpose)? Any other reason not to take the easy way out and simply use a GUID? Thanks for your help.

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• OpenGL fast texture drawing with vertex buffer objects. Is this the way to do it?

  - by Matthew Mitchell

  Hello. I am making a 2D game with OpenGL. I would like to speed up my texture drawing by using VBOs. Currently I am using the immediate mode. I am generating my own coordinates when I rotate and scale a texture. I also have the functionality of rounding the corners of a texture, using the polygon primitive to draw those. I was thinking, would it be fastest to make a VBO with vertices for the sides of the texture with no offset included so I can then use glViewport, glScale (Or glTranslate? What is the difference and most suitable here?) and glRotate to move the drawing position for my texture. Then I can use the same VBO with no changes to draw the texture each time. I could only change the VBO when I need to add coordinates for the rounded corners. Is that the best way to do this? What things should I look out for while doing it? Is it really fastest to use GL_TRIANGLES instead of GL_QUADS in modern graphics cards? Thank you for any answer.

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• Change HTML image into a Button for partial refresh of page

  - by user990951

  I am new to webpage design and MVC. I have a aspx page and I have a html image. I want to change this image and make it clickable so that it will refresh only the bottom half of the page when clicked. I setup my image so that the source of the image is updated by the controller. By using the following src="<%=ViewData["BookImg"] %>" So that the whole story is clear. When a person clicks on the image of the book, it displays on the bottom half of the page information about that book pulled from a sql database. I am thinking that I would need to look into getting ajax implemented so that I can do partial page update. But the question is how do I change that HTML image into a button. Thanks in advance. ---updating per the answer chosen but still having problems--- home.aspx <% Html.RenderPartial("HomePartialView"); %> <img id = "Book_Img" src="<%=ViewData["BookImg"] %>" alt = "click Me" class="imgClick"/> <script src="../../Scripts/jquery-1.5.1.js" type="text/javascript"> $(document).ready(function(){ $(".imgClick").click(function () { $("HomePartialView").load("../../Controllers/HomeController/PartialViewBook"); }); }); </script> ---Controller public ActionResult PartialViewBook() { ViewData[imageBookPressd] = "hello world"; return View("HomePartialView"); }

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• How do I make a HTTP POST request to an url from within a c++ dll?

  - by tjorriemorrie

  Hi, there's an open-source application I need to use. It allows you to use a custom dll. Unfortunately, I can't code c++; i don't like it; it don't want to learn it. I do know PHP very well however, thus you can see that I'll rather do my logic within a PHP application. Thus I'm thinking about posting the data from c++/dll to a url on my localhost. (i have my local server set up, that's not the problem). I need to post a large amount of variables (thus a POST and not GET request required). The return value will only be one (int)variable, either 0, 1 or 2. So I need a c++ function that: 1) will post variables to an url. 2) Wait for, and receive the answer. The data type can be in xml, soap, json, whatever, doesn't matter. Is there anyone that can write a little c++ http function for me? pretty please? ;)

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• Project Euler, Problem 10 java solution now working

  - by Dennis S

  Hi, I'm trying to find the sum of the prime numbers < 2'000'000. This is my solution in java but I can't seem get the correct answer. Please give some input on what could be wrong and general advice on the code is appreciated. Printing 'sum' gives: 1308111344, which is incorrect. /* The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. */ class Helper{ public void run(){ Integer sum = 0; for(int i = 2; i < 2000000; i++){ if(isPrime(i)) sum += i; } System.out.println(sum); } private boolean isPrime(int nr){ if(nr == 2) return true; else if(nr == 1) return false; if(nr % 2 == 0) return false; for(int i = 3; i < Math.sqrt(nr); i += 2){ if(nr % i == 0) return false; } return true; } } class Problem{ public static void main(String[] args){ Helper p = new Helper(); p.run(); } }

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• Random Movement in a Fixed Container

  - by James Barracca

  I'm looking to create something that can move randomly inside of a fixed div container. I love the way the object moves in this example that I found searching this website... http://jsfiddle.net/Xw29r/15/ The code on the jsfiddle contains the following: $(document).ready(function(){ animateDiv(); }); function makeNewPosition(){ // Get viewport dimensions (remove the dimension of the div) var h = $(window).height() - 50; var w = $(window).width() - 50; var nh = Math.floor(Math.random() * h); var nw = Math.floor(Math.random() * w); return [nh,nw]; } function animateDiv(){ var newq = makeNewPosition(); var oldq = $('.a').offset(); var speed = calcSpeed([oldq.top, oldq.left], newq); $('.a').animate({ top: newq[0], left: newq[1] }, speed, function(){ animateDiv(); }); }; function calcSpeed(prev, next) { var x = Math.abs(prev[1] - next[1]); var y = Math.abs(prev[0] - next[0]); var greatest = x > y ? x : y; var speedModifier = 0.1; var speed = Math.ceil(greatest/speedModifier); return speed; }? CSS: div.a { width: 50px; height:50px; background-color:red; position:fixed; }? However, I don't believe the code above constricts that object at all. I need my object to move randomly inside of a container that is let's say for now... 1200px in width and 500px in height. Can someone steer me in the right direction? I'm super new to coding so I'm having a hard time finding an answer on my own. Thanks so much! James

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• Element not found blocks execution in Selenium

  - by Mariano

  In my test, I try to verify if certain text exists (after an action) using find_element_by_xpath. If I use the right expression and my test pass, the routine ends correctly in no time. However if I try a wrong text (meaning that the test will fail) it hangs forever and I have to kill the script otherwise it does not end. Here is my test (the expression Thx user, client or password you entered is incorrect does not exist in the system, no matter what the user does): # -*- coding: utf-8 -*- import gettext import unittest from selenium import webdriver class TestWrongLogin(unittest.TestCase): def setUp(self): self.driver = webdriver.Firefox() self.driver.get("http://10.23.1.104:8888/") # let's check the language try: self.lang = self.driver.execute_script("return navigator.language;") self.lang = self.lang("-")[0] except: self.lang = "en" language = gettext.translation('app', '/app/locale', [self.lang], fallback=True) language.install() self._ = gettext.gettext def tearDown(self): self.driver.quit() def test_wrong_client(self): # test wrong client inputElement = self.driver.find_element_by_name("login") inputElement.send_keys("root") inputElement = self.driver.find_element_by_name("client") inputElement.send_keys("Unleash") inputElement = self.driver.find_element_by_name("password") inputElement.send_keys("qwerty") self.driver.find_element_by_name("form.submitted").click() # wait for the db answer self.driver.implicitly_wait(10) ret = self.driver.find_element_by_xpath( "//*[contains(.,'{0}')]".\ format(self._(u"Thx user, client or password you entered is incorrect"))) self.assertTrue(isinstance(ret, webdriver.remote.webelement.WebElement)) if __name__ == '__main__': unittest.main() Why does it do that and how can I prevent it?

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• If attacker has original data, and encrypted data, can they determine the passphrase?

  - by Brad Cupit

  If an attacker has several distinct items (for example: e-mail addresses) and knows the encrypted value of each item, can the attacker more easily determine the secret passphrase used to encrypt those items? Meaning, can they determine the passphrase without resorting to brute force? This question may sound strange, so let me provide a use-case: User signs up to a site with their e-mail address Server sends that e-mail address a confirmation URL (for example: https://my.app.com/confirmEmailAddress/bill%40yahoo.com) Attacker can guess the confirmation URL and therefore can sign up with someone else's e-mail address, and 'confirm' it without ever having to sign in to that person's e-mail account and see the confirmation URL. This is a problem. Instead of sending the e-mail address plain text in the URL, we'll send it encrypted by a secret passphrase. (I know the attacker could still intercept the e-mail sent by the server, since e-mail are plain text, but bear with me here.) If an attacker then signs up with multiple free e-mail accounts and sees multiple URLs, each with the corresponding encrypted e-mail address, could the attacker more easily determine the passphrase used for encryption? Alternative Solution I could instead send a random number or one-way hash of their e-mail address (plus random salt). This eliminates storing the secret passphrase, but it means I need to store that random number/hash in the database. The original approach above does not require this extra table. I'm leaning towards the the one-way hash + extra table solution, but I still would like to know the answer: does having multiple unencrypted e-mail addresses and their encrypted counterparts make it easier to determine the passphrase used?

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• .Net Inherited Control Property Default

  - by Yisman

  Hello fellows Im trying to make a simple "ButtonPlus" control. the main idea is to inherit from the button control and add some default property values (such as font,color,padding...) No matter how i try, the WinForm always generates (or "serializes") the property value in the client forms the whole point is to have minimal and clean code, not that every instance of the buttonPlus should have 5 lines of init code. I want that the form designer should not generate any code for theses properties and be able to control them from the ButtonPlus code. In other words, if I change the ForeColor from red to blue only 1 single bingle line of code in the app should change. heres my code so far. as you can see, ive tried using defaultvalue, reset , shouldserialize.... anything i was able to find on the web! Public Class ButtonPlus Inherits Button Sub New() 'AutoSize = True AutoSizeMode = Windows.Forms.AutoSizeMode.GrowAndShrink Font = New System.Drawing.Font("Arial", 11.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(177, Byte)) Padding = New System.Windows.Forms.Padding(3) Anchor = AnchorStyles.Left + AnchorStyles.Right + AnchorStyles.Top ForeColor = Color.Aqua End Sub ' _ 'Public Overrides Property AutoSize() As Boolean ' Get ' Return MyBase.AutoSize ' End Get ' Set(ByVal value As Boolean) ' MyBase.AutoSize = value ' End Set 'End Property Public Function ShouldSerializeAutoSize() As Boolean Return False ' Not AutoSize = True End Function Public Function ShouldSerializeForeColor() As Boolean Return False 'Not ForeColor = Color.Aqua End Function Public Overrides Sub ResetForeColor() ForeColor = Color.Aqua End Sub End Class Thank you very much for taking the time to look this over and answer all the best

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• Fastest way to perform subset test operation on a large collection of sets with same domain

  - by niktech

  Assume we have trillions of sets stored somewhere. The domain for each of these sets is the same. It is also finite and discrete. So each set may be stored as a bit field (eg: 0000100111...) of a relatively short length (eg: 1024). That is, bit X in the bitfield indicates whether item X (of 1024 possible items) is included in the given set or not. Now, I want to devise a storage structure and an algorithm to efficiently answer the query: what sets in the data store have set Y as a subset. Set Y itself is not present in the data store and is specified at run time. Now the simplest way to solve this would be to AND the bitfield for set Y with bit fields of every set in the data store one by one, picking the ones whose AND result matches Y's bitfield. How can I speed this up? Is there a tree structure (index) or some smart algorithm that would allow me to perform this query without having to AND every stored set's bitfield? Are there databases that already support such operations on large collections of sets?

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• Linux apache developing configuration

  - by Jeffrey Vandenborne

  Recenly reinstalled my system, and came to a point where I need apache and php. I've been searching a long time, but I can't figure out how to configure apache the best way for a developer computer. The plan is simple, I want to install apache 2 + mysql server so I can develop some php website. I don't want to install lamp though, just the apache2, php5 and mysql. The problem that I've been looking an answer for is the permissions on the /var/www/ folder. I've tried making it my folder using the chown command, followed by a chmod -R 755 /var/www. Most things work then, but fwrite for example won't work, because I need to give write permissions to everyone, unless I change my global umask to 000 I'm not sure what I can do. In short: I want to install apache2, php5, mysql-server without using lamp, but configured in a way so I can open up netbeans, start a project with root in /var/www/, and run every single function without permission faults. Does anyone have experiences or workarounds to this? Extra: OS: Ubuntu 10.04 ARCH: x86_64

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• `this` in global scope in ECMAScript 6

  - by Nathan Wall

  I've tried looking in the ES6 draft myself, but I'm not sure where to look: Can someone tell me if this in ES6 necessarily refers to the global object? Will this object have same members as the global scope? If you could answer for ES5 that would be helpful as well. I know this in global scope refers to the global object in the browser and in most other ES environments, like Node. I just want to know if that's the defined behavior by the spec or if that's extended behavior that implementers have added (and if this behavior will continue in ES6 implementations). In addition, is the global object always the same thing as the global scope? Or are there distinctions? Update - Why I want to know: I am basically trying to figure out how to get the global object reliably in ES5 & 6. I can't rely on window because that's specific to the browser, nor can I rely on global because that's specific to environments like Node. I know this in Node can refer to module in module scope, but I think it still refers to global in global scope. I want a cross-environment ES5 & 6 compliant way to get the global object (if possible). It seems like in all the environments I know of this in global scope does that, but I want to know if it's part of the actual spec (and so reliable across any environment that I may not be familiar with). I also need to know if the global scope and the global object are the same thing by the spec. In other words will all variables in global scope be the same as globalobject.variable_name?

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• Inline function v. Macro in C -- What's the Overhead (Memory/Speed)?

  - by Jason R. Mick

  I searched Stack Overflow for the pros/cons of function-like macros v. inline functions. I found the following discussion: Pros and Cons of Different macro function / inline methods in C ...but it didn't answer my primary burning question. Namely, what is the overhead in c of using a macro function (with variables, possibly other function calls) v. an inline function, in terms of memory usage and execution speed? Are there any compiler-dependent differences in overhead? I have both icc and gcc at my disposal. My code snippet I'm modularizing is: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = AttractiveTerm * AttractiveTerm; EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); My reason for turning it into an inline function/macro is so I can drop it into a c file and then conditionally compile other similar, but slightly different functions/macros. e.g.: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = pow(SigmaSquared/RadialDistanceSquared,9); EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); (note the difference in the second line...) This function is a central one to my code and gets called thousands of times per step in my program and my program performs millions of steps. Thus I want to have the LEAST overhead possible, hence why I'm wasting time worrying about the overhead of inlining v. transforming the code into a macro. Based on the prior discussion I already realize other pros/cons (type independence and resulting errors from that) of macros... but what I want to know most, and don't currently know is the PERFORMANCE. I know some of you C veterans will have some great insight for me!!

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• C++ polymorphism, function calls

  - by moai

  Okay, I'm pretty inexperienced as a programmer, let alone in C++, so bear with me here. What I wanted to do was to have a container class hold a parent class pointer and then use polymorphism to store a child class object. The thing is that I want to call one of the child class's functions through the parent class pointer. Here's a sort of example of what I mean in code: class SuperClass { public: int x; } class SubClass : public SuperClass { public: void function1() { x += 1; } } class Container { public: SuperClass * alpha; Container(SuperClass& beta) { alpha = beta; } } int main() { Container cont = new Container(new SubClass); } (I'm not sure that's right, I'm still really shaky on pointers. I hope it gets the point across, at least.) So, I'm not entirely sure whether I can do this or not. I have a sneaking suspicion the answer is no, but I want to be sure. If someone has another way to accomplish this sort of thing, I'd be glad to hear it.

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• jQuery: AJAX call isn't updating page

  - by Cortopasta

  Thought I had a simple AJAX call using $.POST(), but apparently my function isn't firing, and nothing is updating :-/ Here is the call: $(".answerVerse ul li").click(function(){ var rank = $(this).removeClass("star_empty star_full star_highlight").attr("class"); var verse_id = $(this).parent().parent().find(".verseId").html(); var answer_id = $(this).parent().parent().find(".answerId").html(); var place = this; $.post("rank.php", { rank: rank, verse_id: verse_id, answer_id: answer_id },function(data){ $(place).parent().removeClass().addClass(data.newVerseRank); for (i=0;i<=5;i++) { $(".answerVerse ul."+i).each(function(){ $(".answerVerse ul."+i+" li."+i).prevAll().andSelf().removeClass("star_empty").addClass("star_full"); }); } }, "json"); }); And here is the PHP (rank.php) that it calls: require_once("dbcon.php"); $user = new user(); $user->updateVerseRank($_POST['verse_id'], $_POST['rank']); $user->getVerse($_POST['verse_id']); $user->getAnswer($_POST['answer_id']; $arr = array ('newVerseRank'=>htmlspecialchars(round($user->verse[3])),'newVerseVotes'=>htmlspecialchars(round($user->verse[4])),'newAnswerRank'=>htmlspecialchars($user->answer[3])); echo json_encode($arr); Why am I not updating the page? I know it's something dumb I'm doing seeing as how this is my first attempt at AJAX and JSON :-/ Just trying to learn

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• How to get the set of beans that are to be created in Spring?

  - by cyborg

  So here's the scenario: I have a Spring XML configuration with some lazy-beans, some not lazy-beans and some beans that depend on other beans. Eventually Spring will resolve all this so that only the beans that are meant to be created are created. The question: how can I programmatically tell what this set is? When I use context.getBean(name) that initializes the bean. BeanDefinition.isLazyInit() will only tell me how I defined the bean. Any other ideas? ETA: In DefaultListableBeanFactory: public void preInstantiateSingletons() throws BeansException { if (this.logger.isInfoEnabled()) { this.logger.info("Pre-instantiating singletons in " + this); } synchronized (this.beanDefinitionMap) { for (Iterator it = this.beanDefinitionNames.iterator(); it.hasNext();) { String beanName = (String) it.next(); RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName); if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) { if (isFactoryBean(beanName)) { FactoryBean factory = (FactoryBean) getBean(FACTORY_BEAN_PREFIX + beanName); if (factory instanceof SmartFactoryBean && ((SmartFactoryBean) factory).isEagerInit()) { getBean(beanName); } } else { getBean(beanName); } } } } } The set of instantiable beans is initialized. When initializing this set any beans not in this set referenced by this set will also be created. From looking through the source it does not look like there's going to be any easy way to answer my question.

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• OpenSource Projects - Is there a site which lists projecs that need more developers?

  - by Jamie

  Morning/Afternoon/Evening all, Do any of you know of a website which lists opensource projects which are in need of more help? Let me elaborate, I would like to work on another open source project (I already work on a couple), however, it would be nice to have a site which lists lots of OS projects, their aims, deadlines, workload, how many more developers they are in need of etc. Of course, I could just pick a topic i'm interested in, find an OS project and then work on it, however, it would be nice to see a diversified list of projects. Primarily because some little known awesome projects get little attention and big projects such as jQuery forks, adium, gimp etc. etc. get a lot of attention because they are well known (and of course because they are great)and thus get a lot of developers working on them. It would be nice to see some little known projects getting more attention and thus hopefully drawing some people to work on them. Currently there are many websites hosting os projects, such as github, sourceforge, google code etc. A website to centralise all of this into one place and categorise it would be awesome. Let me know your thoughts please. I'm not looking for an answer per se, so I will mark it is as a community wiki. Your thoughts would be great.

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• How to catch unintentional function interpositioning?

  - by SiegeX

  Reading through my book Expert C Programming, I came across the chapter on function interpositioning and how it can lead to some serious hard to find bugs if done unintentionally. The example given in the book is the following: my_source.c mktemp() { ... } main() { mktemp(); getwd(); } libc mktemp(){ ... } getwd(){ ...; mktemp(); ... } According to the book, what happens in main() is that mktemp() (a standard C library function) is interposed by the implementation in my_source.c. Although having main() call my implementation of mktemp() is intended behavior, having getwd() (another C library function) also call my implementation of mktemp() is not. Apparently, this example was a real life bug that existed in SunOS 4.0.3's version of lpr. The book goes on to explain the fix was to add the keyword static to the definition of mktemp() in my_source.c; although changing the name altogether should have fixed this problem as well. This chapter leaves me with some unresolved questions that I hope you guys could answer: Does GCC have a way to warn about function interposition? We certainly don't ever intend on this happening and I'd like to know about it if it does. Should our software group adopt the practice of putting the keyword static in front of all functions that we don't want to be exposed? Can interposition happen with functions introduced by static libraries? Thanks for the help. EDIT I should note that my question is not just aimed at interposing over standard C library functions, but also functions contained in other libraries, perhaps 3rd party, perhaps ones created in-house. Essentially, I want to catch any instance of interpositioning regardless of where the interposed function resides.

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• Are C++ exceptions sufficient to implement thread-local storage?

  - by Potatoswatter

  I was commenting on an answer that thread-local storage is nice and recalled another informative discussion about exceptions where I supposed The only special thing about the execution environment within the throw block is that the exception object is referenced by rethrow. Putting two and two together, wouldn't executing an entire thread inside a function-catch-block of its main function imbue it with thread-local storage? It seems to work fine: #include <iostream> #include <pthread.h> using namespace std; struct thlocal { string name; thlocal( string const &n ) : name(n) {} }; thlocal &get_thread() { try { throw; } catch( thlocal &local ) { return local; } } void print_thread() { cerr << get_thread().name << endl; } void *kid( void *local_v ) try { thlocal &local = * static_cast< thlocal * >( local_v ); throw local; } catch( thlocal & ) { print_thread(); return NULL; } int main() try { thlocal local( "main" ); throw local; } catch( thlocal & ) { print_thread(); pthread_t th; thlocal kid_local( "kid" ); pthread_create( &th, NULL, &kid, &kid_local ); pthread_join( th, NULL ); print_thread(); return 0; } Is this novel or well-characterized? Was my initial premise correct? What kind of overhead does get_thread incur in, say, GCC and VC++? It would require throwing only exceptions derived from struct thlocal, but altogether this doesn't feel like an unproductive insomnia-ridden Sunday morning…

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• Move SELECT to SQL Server side

  - by noober

  Hello all, I have an SQLCLR trigger. It contains a large and messy SELECT inside, with parts like: (CASE WHEN EXISTS(SELECT * FROM INSERTED I WHERE I.ID = R.ID) THEN '1' ELSE '0' END) AS IsUpdated -- Is selected row just added? as well as JOINs etc. I like to have the result as a single table with all included. Question 1. Can I move this SELECT to SQL Server side? If yes, how to do this? Saying "move", I mean to create a stored procedure or something else that can be executed before reading dataset in while cycle. The 2 following questions make sense only if answer is "yes". Why do I want to move SELECT? First off, I don't like mixing SQL with C# code. At second, I suppose that server-side queries run faster, since the server have more chances to cache them. Question 2. Am I right? Is it some sort of optimizing? Also, the SELECT contains constant strings, but they are localizable. For instance, WHERE R.Status = "Enabled" "Enabled" should be changed for French, German etc. So, I want to write 2 static methods -- OnCreate and OnDestroy -- then mark them as stored procedures. When registering/unregistering my assembly on server side, just call them respectively. In OnCreate format the SELECT string, replacing {0}, {1}... with required values from the assembly resources. Then I can localize resources only, not every script. Question 3. Is it good idea? Is there an existing attribute to mark methods to be executed by SQL Server automatically after (un)registartion an assembly? Regards,

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• Best practices for (over)using Azure queues

  - by John

  Hi, I'm in the early phases of designing an Azure-based application. One of the things that attracts me to Azure is the scalability, given the variability of the demand I'm likely to expect. As such I'm trying to keep things loosely coupled so I can add instances when I need to. The recommendations I've seen for architecting an application for Azure include keeping web role logic to a minimum, and having processing done in worker roles, using queues to communicate and some sort of back-end store like SQL Azure or Azure Tables. This seems like a good idea to me as I can scale up either or both parts of the application without any issue. However I'm curious if there are any best practices (or if anyone has any experiences) for when it's best to just have the web role talk directly to the data store vs. sending data by the queue? I'm thinking of the case where I have a simple insert to do from the web role - while I could set this up as a message, send it on the queue, and have a worker role pick it up and do the insert, it seems like a lot of double-handling. However I also appreciate that it may be the case that this is better in the long run, in case the web role gets overwhelmed or more complex logic ends up being required for the insert. I realise this might be a case where the answer is "it depends entirely on the situation, check your perf metrics" - but if anyone has any thoughts I'd be very appreciative! Thanks John

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• Use SQL to clone a tree structure represented in a database

  - by AmoebaMan17

  Given a table that represents a hierarchical tree structure and has three columns ID (Primary Key, not-autoincrementing) ParentGroupID SomeValue I know the lowest most node of that branch, and I want to copy that to a new branch with the same number of parents that also need to be cloned. I am trying to write a single SQL INSERT INTO statement that will make a copy of every row that is of the same main has is part one GroupID into a new GroupID. Example beginning table: ID | ParentGroupID | SomeValue ------------------------ 1 | -1 | a 2 | 1 | b 3 | 2 | c Goal after I run a simple INSERT INTO statement: ID | ParentGroupID | SomeValue ------------------------ 1 | -1 | a 2 | 1 | b 3 | 2 | c 4 | -1 | a-cloned 5 | 4 | b-cloned 6 | 5 | c-cloned Final tree structure +--a (1) | +--b (2) | +--c (3) | +--a-cloned (4) | +--b-cloned (5) | +--c-cloned (6) The IDs aren't always nicely spaced out as this demo data is showing, so I can't always assume that the Parent's ID is 1 less than the current ID for rows that have parents. Also, I am trying to do this in T-SQL (for Microsoft SQL Server 2005 and greater). This feels like a classic exercise that should have a pure-SQL answer, but I'm too used to programming that my mind doesn't think in relational SQL.

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• Dynamic use of :default_url in Paperclip

  - by dgilperez

  I'm trying to configure Paperclip to provide different missing images based on the instance's category attribute. Every category of the object has its own missing image. This is my first take: EDIT to add full models: class Service < ActiveRecord::Base attr_accessible :logo, :logo_file_name, :logo_content_type, :logo_file_size, :logo_updated_at belongs_to :category, :counter_cache => true has_attached_file :logo, :path => "/:id-:style-:filename", :url => ":s3_eu_url", :default_url => "/logos/:style/#{self.category.name]}.png", :styles => { :large => "600x400>", :medium => "300x200>", :small => "100x75>", :thumb => "60x42>" } end class Category < ActiveRecord::Base attr_accessible nil has_many :services end In my view, image_tag service.logo.url(:thumb) outputs: undefined method `category' for #<Class:0x0000010a731620> Any ideas? EDIT2: A working default_url is :default_url => "/logos/:style/missing.png", SOLUTION: See my own answer below.

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