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How to make gcc on SUN calculate floating points the same way as in Linux

- by Marina

I have a project where I have to perform some mathematics calculations with double variables. The problem is that I get different results on SUN Solaris 9 and Linux. There are a lot of ways (explained here and other forums) how to make Linux work as Sun, but not the other way around. I cannot touch the Linux code, so it is only SUN I can change. Is there any way to make SUN to behave as Linux? The code I run(compile with gcc on both systems): int hash_func(char *long_id) { double product, lnum, gold; while (*long_id) lnum = lnum * 10.0 + (*long_id++ - '0'); printf("lnum => %20.20f\n", lnum); lnum = lnum * 10.0E-8; printf("lnum => %20.20f\n", lnum); gold = 0.6125423371582974; product = lnum * gold; printf("product => %20.20f\n", product); ... } if the input is 339886769243483 the output in Linux: lnum => 339886769243**483**.00000000000000000000 lnum => 33988676.9243**4829473495483398** product => 20819503.600158**59827399253845** When on SUN: lnum => 339886769243483.00000000000000000000 lnum => 33988676.92434830218553543091 product = 20819503.600158**60199928283691** Note: The result is not always different, moreover most of the times it is the same. Just 10 15-digit numbers out of 60000 have this problem. Please help!!!

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how to make sure the non disclosure agreement is read

- by Xin Qian Ch'ang

Every time a user registers to our site we need to show a non-disclosure agreement. In order to continue the user has to accept it. My issue is that I have the NDA in all one page and the user does not really read it and accept (like we all do). What I want is to make sure the user reads the NDA and accepts it one he "read" it? What I have now is a simple jqeury validation if the user checks a box and click on accept. then it goes to the next page. Here's what i have <script> $(document).ready(function() { $('#go').click(function() { // check if checkbox is check and go to next page }); }); </script> <div> full nda <hr> <input type=checkbox> <input type=button value=go id=go> </div> Thanks

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Java: Implement own message queue (threadsafe)

- by derMax

The task is to implement my own messagequeue that is thread safe. My approach: public class MessageQueue { /** * Number of strings (messages) that can be stored in the queue. */ private int capacity; /** * The queue itself, all incoming messages are stored in here. */ private Vector<String> queue = new Vector<String>(capacity); /** * Constructor, initializes the queue. * * @param capacity The number of messages allowed in the queue. */ public MessageQueue(int capacity) { this.capacity = capacity; } /** * Adds a new message to the queue. If the queue is full, it waits until a message is released. * * @param message */ public synchronized void send(String message) { //TODO check } /** * Receives a new message and removes it from the queue. * * @return */ public synchronized String receive() { //TODO check return "0"; } } If the queue is empty and I call remove(), I want to call wait() so that another thread can use the send() method. Respectively, I have to call notifyAll() after every iteration. Question: Is that possible? I mean does it work that when I say wait() in one method of an object, that I can then execute another method of the same object? And another question: Does that seem to be clever?

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XMPP4R Callbacks dont seem to work

- by Sid

Im using xmpp4r and trying to get the hang of a basic chat feature that I wish to implement later in my Rails app. My fundamentals on Ruby Threads is still a bit shaky so I would appreciate any help on this. Though I register the callback i dont get a response from my gmail account. I am able to send a message but my ruby program terminates. In order to prevent it from terminating I tried to stop on of the threads in the program but I cant seem to get it working. require 'rubygems' require "xmpp4r/client" require "xmpp4r/roster" include Jabber def connect client = Client.new(JID::new("[email protected]")) client.connect client.auth("test") client.send(Presence.new.set_type(:available)) client end def create_message(message, to_email) msg = Jabber::Message::new(to_email, message) msg.type = :chat msg end def subscribe(email_id) pres = Presence.new.set_type(:subscribe).set_to(email_id) pres end client = connect roster = Roster::Helper.new(client) roster.add_subscription_request_callback do |item,pres| roster.accept_subscription(pres.from) end def create_callback(client) $t4= Thread.new do client.add_message_callback do |m| puts m.body puts "................................Callback working" end end end puts "Client has connected" msg = create_message("Welcome to the winter of my discontent", "[email protected]") client.send(msg) create_callback(client) def check(client) $t3 = Thread.new do loop do puts "t3 still running........." Thread.current.stop $t4.join end end end check(client)

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Why is it not good to use $_SESSION in Restful Implementations?

- by keisimone

Original Question: i read that for RESTful websites. it is not good to use $_SESSION. Why is it not good? how then do i properly authenticate users without looking up database all the time to check for the user's roles? I read that it is not good to use $_SESSION. http://www.recessframework.org/page/towards-restful-php-5-basic-tips I am creating a WEBSITE, not web service in PHP. and i am trying to make it more RESTful. at least in spirit. right now i am rewriting all the action to use Form tags POST and add in a hidden value called _method which would be "delete" for deleting action and "put" for updating action. however, i am not sure why it is recommended NOT to use $_SESSION. i would like to know why and what can i do to improve. To allow easy authorization checking, what i did was to after logging in the user, the username is stored in the $_SESSION. Everytime the user navigates to a page, the page would check if the username is stored inside $_SESSION and then based on the $_SESSION retrieves all the info including privileges from the database and then evaluates the authorization to access the page based on the info retrieved. Is the way I am implementing bad? not RESTful? how do i improve performance and security? Thank you.

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Running an executable on network share with CustomAction with wix?

- by martin

Hello, i have created a msi-package which compresses some xml-files to a zip-file during installation. I have created a CustomAction for this purposes: <CustomAction Id="CompressMy" BinaryKey="zipEXE" ExeCommand="a -tzip "[TEMPLATE_DIR]my.zip" "[TempSourceFolder]data.xml"" Return="check" HideTarget="no" Impersonate="no" Execute="deferred" /> The installation works fine, if i try to install to a local drive, but recently a customer wanted to install [TEMPLATE_DIR] to a network drive on Windows Vista. The CustomAction fails, because of the elevated install-user hasn't mapped the network drive, even if the installer-calling user has mapped the drive. This happens also, if I try to install to an unc-path. I use 7zip for compressing. I have added it to my msi-package. I have tried to set Impersonate="yes", but then the Installations fails, if my TEMPLATE_DIR is f.e. the ProgramData-dir. Do you have any idea what i can do? I thinked about checking if TEMPLATE_DIR is a network path, but I didn't know how i can check this. Or do you have any other Ideas how I can provide a local and a network installation while using this custom action. Would be great if there are any advices, greetings, Martin

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Can parser combinators be made efficient?

- by Jon Harrop

Around 6 years ago, I benchmarked my own parser combinators in OCaml and found that they were ~5× slower than the parser generators on offer at the time. I recently revisited this subject and benchmarked Haskell's Parsec vs a simple hand-rolled precedence climbing parser written in F# and was surprised to find the F# to be 25× faster than the Haskell. Here's the Haskell code I used to read a large mathematical expression from file, parse and evaluate it: import Control.Applicative import Text.Parsec hiding ((<|>)) expr = chainl1 term ((+) <$ char '+' <|> (-) <$ char '-') term = chainl1 fact ((*) <$ char '*' <|> div <$ char '/') fact = read <$> many1 digit <|> char '(' *> expr <* char ')' eval :: String -> Int eval = either (error . show) id . parse expr "" . filter (/= ' ') main :: IO () main = do file <- readFile "expr" putStr $ show $ eval file putStr "\n" and here's my self-contained precedence climbing parser in F#: let rec (|Expr|) (P(f, xs)) = Expr(loop (' ', f, xs)) and loop = function | ' ' as oop, f, ('+' | '-' as op)::P(g, xs) | (' ' | '+' | '-' as oop), f, ('*' | '/' as op)::P(g, xs) -> let h, xs = loop (op, g, xs) let op = match op with | '+' -> (+) | '-' -> (-) | '*' -> (*) | '/' -> (/) loop (oop, op f h, xs) | _, f, xs -> f, xs and (|P|) = function | '('::Expr(f, ')'::xs) -> P(f, xs) | c::xs when '0' <= c && c <= '9' -> P(int(string c), xs) My impression is that even state-of-the-art parser combinators waste a lot of time back tracking. Is that correct? If so, is it possible to write parser combinators that generate state machines to obtain competitive performance or is it necessary to use code generation?

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Problem with load testing Web Service - VSTS 2008

- by Carlos

Hello, I have a webtest with makes a simple call to a WebService which looks like that: MyWebService webService = new MyWebService(); webService.Timeout = 180000; webService.myMethod(); I am not using ThinkTimes, also the Run Duration is set to 5 minutes. When I ran this test simulating only 1 user, I check the counters and I found something like that: Tests Total: 4500 Network Interface\Bytes sent (agent machine): 35,500 Then I ran the same tests, but this time simulating 2 users and I got something like that: Tests Total: 2225 Network Interface\Bytes sent (agent machine): 30,500 So when I increased the numbers of users the tests/sec was half than when I use only 1 user and the bytes sent by the agent was also lower. I think it is strange, because it doesn't seems I have a bottleneck in my agent machine since CPU is never higher than 30% and I have over 1.5GB of RAM free, also my network utilization is like 0.5% of its capacity. In order to troubleshot this I ran a test using Step Pattern, the simulated users went from 20 to 800 users. When I check the requests/sec it is practically constant through the whole test, so it is clear there is something in my test or my environment which is preventing the number of requests from gets higher. It would be a expected behavior if the "response time" was getting higher because it would tell me the requests wasn't been processed properly, but the strange thing is the response time is practically constant all the time and it is pretty low actually. I have no idea why my agent can't send more requests when I increase the numbers of users, any help/tip/guess would be really appreciate.

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Second Thread Holding Up Entire Program in C# Windows Form Application

- by Brandon

In my windows form application, I'm trying to test the user's ability to access a remote machine's shared folder. The way I'm doing this (and I'm sure that there are better ways...but I don't know of them) is to check for the existence of a specific directory on the remote machine (I'm doing this because of firewall/other security restrictions that I'm confronted with in my organization). If the user has rights to access the shared folder, then it returns in no time at all, but if they don't, it hangs forever. To solve this, I threw the check into another thread and wait only 1000 milliseconds before determining that the share can't be hit by the user. However, when I do this, it still hangs as if it was never run in the same thread. What is making it hang and how do I fix it? I would think that the fact that it is in a separate thread would allow me to just let the thread finish on it's own in the background. Here is my code: bool canHitInstallPath = false; Thread thread = new Thread(new ThreadStart(() => { canHitInstallPath = Directory.Exists(compInfo.InstallPath); })); thread.Start(); thread.Join(1000); if (canHitInstallPath == false) { throw new Exception("Cannot hit folder: " + compInfo.InstallPath); }

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Use Struct as a Ptr/class? Need a fix .NET

- by acidzombie24

I wrote a bunch of code and i would like to fix it the fastest way possible. I'll describe my problem in a easier way. I have apples and oranges, they are both Point and in the list apples, oranges. I create a PictureBox and draw the apple/oranges on screen and move them around and update the Point via Tag. The problem now is since its a struct the tag is a copy so the original elements in the list are not update. So, how do i update them? I consider using Point? But those seem to be readonly. So the only solution i can think of is Clear the list, iterate through all the controls then check the picturebox property to check if the image is a apple or orange then add it to a list I really only thought of this solution typing this question, but my main question is, is there a better way? Is there some List<Ptr<Point>> class i can use so when i update the apples or oranges through the tag the element in the list will update as a class would?

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How to get resultset with stored procedure calls over two linked servers?

- by räph

I have problems filling a temporary table with the resultset from a procedure call on a linked server, in which again a procedure on another server is called. I have a Stored Procedure sproc1 with the following code, which calls another procedure sproc2 on a linked server. SET @sqlCommand = 'INSERT INTO #tblTemp ( ModuleID, ParamID) ' + '( SELECT * FROM OPENQUERY(' + @targetServer + ', ' + '''SET FMTONLY OFF; EXEC ' + @targetDB + '.usr.sproc2 ' + @param + ''' ) )' exec ( @sqlCommand ) Now in the called sproc2 I again call a third procedure sproc3 on another linked server, which returns my resultset. SET @sqlCommand = 'EXEC ' + @targetServer +'.database.usr.sproc3 ' + @param exec ( @sqlCommand ) The whole thing doen't work, as I get an SQL error 7391 The operation could not be performed because OLE DB provider "%ls" for linked server "%ls" was unable to begin a distributed transaction. I already checked the hints at this microsoft article, but without success. But maybe, I can change the code in sproc1. Would there be some alternative to the temp table and the open query? Just calling stored procedures from server A to B to C and returning the resultset is working (I do this often in the application). But this special case with the temp table and openquery doesn't work! Or is it just not possible what I am trying to do? The microsft article states: Check the object you refer on the destination server. If it is a view or a stored procedure, or causes an execution of a trigger, check whether it implicitly references another server. If so, the third server is the source of the problem. Run the query directly on the third server. If you cannot run the query directly on the third server, the problem is not actually with the linked server query. Resolve the underlying problem first. Is this my case? PS: I can't avoid the architecture with the three servers.

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WriteableBitmap failing badly, pixel array very inaccurate

- by dawmail333

I have tried, literally for hours, and I have not been able to budge this problem. I have a UserControl, that is 800x369, and it contains, simply, a path that forms a worldmap. I put this on a landscape page, then I render it into a WriteableBitmap. I then run a conversion to turn the 1d Pixels array into a 2d array of integers. Then, to check the conversion, I wire up the custom control's click command to use the Point.X and Point.Y relative to the custom control in the newly created array. My logic is thus: wb = new WriteableBitmap(worldMap, new TranslateTransform()); wb.Invalidate(); intTest = wb.Pixels.To2DArray(wb.PixelWidth); My conversion logic is as such: public static int[,] To2DArray(this int[] arr,int rowLength) { int[,] output = new int[rowLength, arr.Length / rowLength]; if (arr.Length % rowLength != 0) throw new IndexOutOfRangeException(); for (int i = 0; i < arr.Length; i++) { output[i % rowLength, i / rowLength] = arr[i]; } return output; } Now, when I do the checking, I get completely and utterly strange results: apparently all pixels are either at values of -1 or 0, and these values are completely independent of the original colours. Just for posterity: here's my checking code: private void Check(object sender, MouseButtonEventArgs e) { Point click = e.GetPosition(worldMap); ChangeNotification(intTest[(int)click.X,(int)click.Y].ToString()); } The result show absolutely no correlation to the path that the WriteableBitmap has rendered into it. The path has a fill of solid white. What the heck is going on? I've tried for hours with no luck. Please, this is the major problem stopping me from submitting my first WP7 app. Any guidance?

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PHP, MySQL: mysql substitute for php in_array function

- by Devner

Hi all, Say if I have an array and I want to check if an element is a part of that array, I can go ahead and use in_array( needle, haystack ) to determine the results. I am trying to see the PHP equivalent of this for my purpose. Now you might have an instant answer for me and you might be tempted to say "Use IN". Yes, I can use IN, but that's not fetching the desired results. Let me explain with an example: I have a column called "pets" in DB table. For a record, it has a value: Cat, dog, Camel (Yes, the column data is a comma separated value). Consider that this row has an id of 1. Now I have a form where I can enter the value in the form input and use that value check against the value in the DB. So say I enter the following comma separated value in the form input: CAT, camel (yes, CAT is uppercase & intentional as some users tend to enter it that way). Now when I enter the above info in the form input and submit, I can collect the POST'ed info and use the following query: $search = $_POST['pets']; $sql = "SELECT id FROM table WHERE pets IN ('$search') "; The above query is not fetching me the row that already exists in the DB (remember the record which has Cat, dog, Camel as the value for the pets column?). I am trying to get the records to act as a superset and the values from the form input as subsets. So in this case I am expecting the id value to show up as the values exist in the column, but this is not happending. Now say if I enter just CAT as the form input and perform the search, it should show me the ID 1 row. Now say if I enter just camel, cAT as the form input and perform the search, it should show me the ID 1 row. How can I achieve the above? Thank you.

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Image Grabbing with False Referer

- by Mr Carl

Hey guys, I'm struggling with grabbing an image at the moment... sounds silly, but check out this link :P http://manga.justcarl.co.uk/A/Oishii_Kankei/31/1 If you get the image URL, the image loads. Go back, it looks like it's working fine, but that's just the browser loading up the cached image. The application was working fine before, I'm thinking they implemented some kind of Referer check on their images. So I found some code and came up with the following... $ref = 'http://www.thesite.com/'; $file = 'theimage.jpg'; $hdrs = array( 'http' = array( 'method' = "GET", 'header'= "accept-language: en\r\n" . "Accept:application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*\/*;q=0.5\r\n" . "Referer: $ref\r\n" . // Setting the http-referer "Content-Type: image/jpeg\r\n" ) ); // get the requested page from the server // with our header as a request-header $context = stream_context_create($hdrs); $fp = fopen($imgChapterPath.$file, 'rb', false, $context); fpassthru($fp); fclose($fp); Essentially it's making up a false referrer. All I'm getting back though is a bunch of gibberish (thanks to fpassthru) so I think it's getting the image, but I'm afraid to say I have no idea how to output/display the collected image. Cheers, Carl

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Inheritance issue with ivar on the iPhone

- by Buffalo

I am using the BLIP/MYNetwork library to establish a basic tcp socket connection between the iPhone and my computer. So far, the code builds and runs correctly in simulator but deploying to device yields the following error: error: property 'delegate' attempting to use ivar '_delegate' declared in super class of 'TCPConnection' @interface TCPConnection : TCPEndpoint { @private TCPListener *_server; IPAddress *_address; BOOL _isIncoming, _checkedPeerCert; TCPConnectionStatus _status; TCPReader *_reader; TCPWriter *_writer; NSError *_error; NSTimeInterval _openTimeout; } /** The delegate object that will be called when the connection opens, closes or receives messages. */ @property (assign) id<TCPConnectionDelegate> delegate; /** The delegate messages sent by TCPConnection. All methods are optional. */ @protocol TCPConnectionDelegate <NSObject> @optional /** Called after the connection successfully opens. */ - (void) connectionDidOpen: (TCPConnection*)connection; /** Called after the connection fails to open due to an error. */ - (void) connection: (TCPConnection*)connection failedToOpen: (NSError*)error; /** Called when the identity of the peer is known, if using an SSL connection and the SSL settings say to check the peer's certificate. This happens, if at all, after the -connectionDidOpen: call. */ - (BOOL) connection: (TCPConnection*)connection authorizeSSLPeer: (SecCertificateRef)peerCert; /** Called after the connection closes. You can check the connection's error property to see if it was normal or abnormal. */ - (void) connectionDidClose: (TCPConnection*)connection; @end @interface TCPEndpoint : NSObject { NSMutableDictionary *_sslProperties; id _delegate; } - (void) tellDelegate: (SEL)selector withObject: (id)param; @end Does anyone know how I would fix this? Would I simply declare _delegate as a public property of the base class "TCPEndPoint"? Thanks for the help ya'll!

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Custom data forms in CakePHP

- by Affian

I'm building a controller to manage group based ACL in CakePHP and when I create or edit a group I want to be able to select what permissions it has. The group data table only stores a group ID and a group Name as the permissions are stored in the ACO/ARO table. I have an array from the ACO that I want to turn into a set of checkboxes so you can check them to allow access from that group to that ACO. So first off, how do I turn this array into a set of checkboxes. The array looks like this: array( [0] => array( [Aco] => array( [alias] => 'alias' [id] => 1) [children] => array ( [0] => array( [Aco]=> ...etc )) [1] => array( ...etc ) My next question is how can I check these once the form has been submitted to the controller to allow the selected actions? [Update] Ok changing the angle of my question, how can I use the Form helper to create forms that are not based on any Model?

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Android strict dependency checks in SDK 17

- by Christine

This is not a question because I already found the answer. The new Android SDK 17 has a stricter dependency check on jar files. At the same time, they added a jar that I think wasn't there before. My project encountered a conflict between the new annotations.jar in the SDK and one that I already used. Replacing one by the other would work, if they have the same origin. My annotations.jar is from jetbrains, via a Guice dependency, so replacing it doesn't work. This is the error I got: [2012-03-22 10:54:27 - MyApp] Jar mismatch! Fix your dependencies [2012-03-22 10:54:46 - MyApp] Found 2 versions of annotations.jar in the dependency list, [2012-03-22 10:54:46 - MyApp] but not all the versions are identical (check is based on SHA-1 only at this time). [2012-03-22 10:54:46 - MyApp] All versions of the libraries must be the same at this time. [2012-03-22 10:54:46 - MyApp] Versions found are: [2012-03-22 10:54:46 - MyApp] Path: /opt/android-sdk-linux_x86/tools/support/annotations.jar [2012-03-22 10:54:46 - MyApp] Length: 1463 [2012-03-22 10:54:46 - MyApp] SHA-1: 6f59fa3a223df6f332bee8b8bffb526f7445018b [2012-03-22 10:54:46 - MyApp] Path: /home/christine/workspace/MyApp/libs/annotations.jar [2012-03-22 10:54:46 - MyApp] Length: 7593 [2012-03-22 10:54:46 - MyApp] SHA-1: e28fe9e70610beb9ef49226a9e56fed7a86e742a [2012-03-22 10:54:46 - MyApp] Jar mismatch! Fix your dependencies

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Read XML with PHP

- by sea_1987

I am trying to check a field in some XML that is returned from an outside. The XML is returned in a variable call $out and when you view the source of the page you get a XML output of the following, <?xml version="1.0" encoding="UTF-8"?> <ResponseBlock Live="FALSE" Version="3.51"> <Response Type="AUTH"> <OperationResponse> <TransactionReference>23-9-1334895</TransactionReference> <TransactionCompletedTimestamp>2010-04-30 15:59:05</TransactionCompletedTimestamp> <AuthCode>AUTH CODE:TEST</AuthCode> <TransactionVerifier>AlaUOS1MOnN/iwc5s2WPDm5ggrCLwesUnHs9h+W0N3CRaln2W6lh+6dtaRFFhLdwfnw6y7lRemyJUYl9a3dpWfzORE6DaZkFMb+dIb0Ne1UxjFEJkrEtjzx/i8KSayrIBrT/yGZOoOT42EZ9loc+UkdGk/pqYvj8bZztvgBNo2Ak=</TransactionVerifier> <Result>1</Result> <SettleStatus>0</SettleStatus> <SecurityResponseSecurityCode>1</SecurityResponseSecurityCode> <SecurityResponsePostCode>1</SecurityResponsePostCode> <SecurityResponseAddress>1</SecurityResponseAddress> </OperationResponse> <Order> <OrderInformation>This is a test order</OrderInformation> <OrderReference>Order0001</OrderReference> </Order> </Response> </ResponseBlock> I want check what value is in the 'Result' field. I am unsure how to access the information using PHP, so far I have, $xml = simplexml_load_string($out); Many Thanks

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PHP DOMDocument Error Handling Problem

- by Jon

I'm having trouble trying to write an if statement for DOM that will check if $html is blank. However whenever the html page does end up blank, it just removes everything that would be below DOM (including what I had to check if it was blank). $html = file_get_contents("http://example.com/"); $dom = new DOMDocument; @$dom->loadHTML($html); $links = $dom->getElementById('dividhere')->getElementsByTagName('img'); foreach ($links as $link) { echo $link->getAttribute('src'); } All this does is grab an image url in the specified div, which works perfectly until the page is a blank html page. I've tried using SimpleHTMLDOM, which didn't work either (it didn't even fetch the image on working pages). Did I happen to miss something with this one or am I just missing something in both? include_once('simple_html_dom.php') $html = file_get_html("http://example.com/"); foreach($html->find('div[id="dividhere"]') as $div) { if(empty($div->src)) { continue; } echo $div->src; }

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ActiveRecord exceptions not rescued

- by zoopzoop

I have the following code block: unless User.exist?(...) begin user = User.new(...) # Set more attributes of user user.save! rescue ActiveRecord::RecordInvalid, ActiveRecord::RecordNotUnique => e # Check if that user was created in the meantime user = User.exists?(...) raise e if user.nil? end end The reason is, as you can probably guess, that multiple processes might call this method at the same time to create the user (if it doesn't already exist), so while the first one enters the block and starts initializing a new user, setting the attributes and finally calling save!, the user might already be created. In that case I want to check again if the user exists and only raise the exception if it still doesn't (= if no other process has created it in the meantime). The problem is, that regularly ActiveRecord::RecordInvalid exceptions are raised from the save! and not rescued from the rescue block. Any ideas? EDIT: Alright, this is weird. I must be missing something. I refactored the code according to Simone's tip to look like this: unless User.find_by_email(...).present? # Here we know the user does not exist yet user = User.new(...) # Set more attributes of user unless user.save # User could not be saved for some reason, maybe created by another request? raise StandardError, "Could not create user for order #{self.id}." unless User.exists?(:email => ...) end end Now I got the following exception: ActiveRecord::RecordNotUnique: Mysql::DupEntry: Duplicate entry '[email protected]' for key 'index_users_on_email': INSERT INTO `users` ... thrown in the line where it says 'unless user.save'. How can that be? Rails thinks the user can be created because the email is unique but then the Mysql unique index prevents the insert? How likely is that? And how can it be avoided?

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Using unset member variables within a class or struct

- by Doug Kavendek

It's pretty nice to catch some really obvious errors when using unset local variables or when accessing a class or struct's members directly prior to initializing them. In visual studio 2008 you get an "uninitialized local variable used" warning at compile-time and get a run-time check failure at the point of access when debugging. However, if you access an uninitialized struct's member variable through one of its functions, you don't get any warnings or assertions. Obviously the easiest solution is don't do that, but nobody's perfect. For example: struct Test { float GetMember() const { return member; } float member; }; Test test; float f1 = test.member; // Raises warning, asserts in VS debugger at runtime float f2 = test.GetMember(); // No problem, just keeps on going This surprised me, but it makes some sense -- the compiler can't assume calling a function on an unused struct is an error, or how else would you initialize or construct it? And anything fancier just quickly brings up so many other complications that it makes sense that it wouldn't bother classifying which functions are ok to call and when, especially just as a debugging help. I know I can set up my own assertions or error checking within the class itself, but that can complicate some simpler structs. Still, it would seem like within the context of the function call, wouldn't it know insides GetMember() that member wasn't initialized yet? I'm assuming it's not only relying on static compile-time deduction, given the Run-Time Check Failure #3 it raises during execution, so based on my current understanding of it it would seem reasonable for the same checks to apply. Is this just a limitation of this specific compiler/debugger (Visual Studio 2008), or more tied to how C++ works?

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Redirect parent of a page from a cfwindow

- by Ryan French

Hi All, I have a page with cfwindow that require the user to be logged in to view the content on the page. The problem at the moment is if the user logs into the site, then does nothing and the session times out, I have no way that I can think of to redirect the parent of the window to the login screen when the user opens it. So far I have tried using cflocation but that has no way of specifying the container that should be redirected (i.e. the page in the window is being redirected but not the windows parent). I have also thought about using a hidden input with a value based on the session which is then check with Body onLoad event but currently this doesnt work with how the pages have been setup. The last option I have is to check the session variable on loading the window and then closing it if the user is not logged in, which will cause the parent to refresh and redirect to login anyway. However I cant find a way to close a cfwindow without using javascript. Thanks for any help you can give.

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Log 2 N generic comparison tree

- by Morano88

Hey! I'm working on an algorithm for Redundant Binary Representation (RBR) where every two bits represent a digit. I designed the comparator that takes 4 bits and gives out 2 bits. I want to make the comparison in log 2 n so If I have X and Y .. I compare every 2 bits of X with every 2 bits of Y. This is smooth if the number of bits of X or Y equals n where (n = 2^X) i.e n = 2,4,8,16,32,... etc. Like this : However, If my input let us say is 6 or 10 .. then it becomes not smooth and I have to take into account some odd situations like this : I have a shallow experience in algorithms .. is there a generic way to do it .. so at the end I get only 2 bits no matter what the input is ? I just need hints or pseudo-code. If my question is not appropriate here .. so feel free to flag it or tell me to remove it. I'm using VHDL by the way!

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requesting ajax via HttpWebRequest

- by Sami Abdelgadir Mohammed

Hi guys: I'm writing a simple application that will download some piece of data from a website then I can use it later for any purpose The following is the request and response copied from Firebug as the browser did that... when u type http://x5.travian.com.sa/ajax.php?f=k7&x=18&y=-186&xx=12&yy=-192 you will get a php file has some data.. But when I make a request with HttpWebRequest I get wrong data (some unknown letters) Can anyone help me in that.. and if I have to make some encodings or what?? I will be so appreciated.. Response Server nginx Date Tue, 04 Jan 2011 23:03:49 GMT Content-Type application/json; charset=UTF-8 Transfer-Encoding chunked Connection keep-alive X-Powered-By PHP/5.2.8 Expires Mon, 26 Jul 1997 05:00:00 GMT Last-Modified Tue, 04 Jan 2011 23:03:49 GMT Cache-Control no-store, no-cache, must-revalidate, post-check=0, pre-check=0 Pragma no-cache Content-Encoding gzip Vary Accept-Encoding Request Host x5.travian.com.sa User-Agent Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13 Accept text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8 Accept-Language en-us,en;q=0.5 Accept-Encoding gzip,deflate Accept-Charset ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive 115 Connection keep-alive Cookie CAD=57878984%231292375897%230%230%23%230; T3E=%3DImYykTN2EzMmhjO5QTM2QDN2oDM1ITOyoDOxIjM4EDN5ITM6gjO4MDOxIWZyQWMipTZu9metl2ctl2c6MDNxADN6MDNxADNjMDNxADNjMDNxADN; orderby_b1=0; orderby_b=0; orderby2=0; orderby=0

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How to setup Continuous Integration and Continuous Deployment for Django projects?

- by ycseattle

Hello, I am researching about how to set up CI and continuous deployment for a small team project for a Django based web application. Here are needs: Developer check in the code into a hosted SVN server (unfuddle.com) A CI server detects new checkin, check out the source, build, run functional tests. If tests all passed, deploy the code to the webserver on Amazon EC2. For now, the CI server is also responsible to run the functional tests. I figured out that I can use Husdon as the CI server, use Selenium to run functional tests, and use Fabric to deploy the build to remote web server in Amazon cloud. I am new to Django development and not very familiar with opensource tools. My questions are: I can find some information to integrate hudson with selenium, but I couldn't find much information on how to integrate Fabric to Hudson as well. Is this setup viable? Do you see problems? How do I integrate and deploy database changes? Most likely in the early stage we will change database schema very often with code changes. I used to use Visual Studio and the database project made it very simple to deploy. I wonder if there is "established, well-supported" way to do that. Thanks!!

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