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  • Embedded Vimeo Video Callbacks

    - by Andrew
    This post is kind of a follow up to a post I made earlier in regards to HTML5 video callbacks. In that thread, I was given a great piece of code that would allow for the browser to be informed of when the video stops playing and then fire off an action (with jQuery). This is the code I'm currently using: $('video.normal').bind('ended', function(){ $(this).fadeOut().queue(function(){ $(this).siblings('.post-video').fadeIn(); $(this).dequeue(); }); }); Which basically fades the video out when it's completed and brings a poster frame of the video (or similar image) back into view. Well, the scope of the project has changed and now the client is asking for true full screen video and different size videos to be delivered based on user connection speed, something that's a little over my head and a lot over budget. So I've been researching and a Vimeo Plus player seems like a great alternative for visitors using a desktop browser (HD embeds, true full screen, and more). Thing is, I need that above code to continue working in some capacity or another, so does the embedded Vimeo player offer a similar callback that I can utilize? Or am I SOL here? Thanks in advance!

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  • Java Concurrency : Synchronized(this) => and this.wait() and this.notify()

    - by jens
    Hello Experts, I would appreciate your help in understand a "Concurrency Example" from: http://forums.sun.com/thread.jspa?threadID=735386 Qute Start: public synchronized void enqueue(T obj) { // do addition to internal list and then... this.notify(); } public synchronized T dequeue() { while (this.size()==0) { this.wait(); } return // something from the queue } Quote End: My Question is: Why is this code valid? = When I synchronize a method like "public synchronized" = then I synchronize on the "Instance of the Object == this". However in the example above: Calling "dequeue" I will get the "lock/monitor" on this Now I am in the dequeue method. As the list is zero, the calling thread will be "waited" From my understanding I have now a deadlock situation, as I will have no chance of ever enquing an object (from an nother thread), as the "dequeue" method is not yet finised and the dequeue "method" holds the lock on this: So I will never ever get the possibility to call "enequeue" as I will not get the "this" lock. Backround: I have exactly the same problem: I have some kind of connection pool (List of Connections) and need to block if all connections are checked. What is the correct way to synchronize the List to block, if size exceeds a limit or is zero? Thank you very much Jens

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  • How do you save images to a Blackberry device via HttpConnection?

    - by Kai
    My script fetches xml via httpConnection and saves to persistent store. No problems there. Then I loop through the saved data to compose a list of image url's to fetch via queue. Each of these requests calls the httpConnection thread as so ... public synchronized void run() { HttpConnection connection = (HttpConnection)Connector.open("http://www.somedomain.com/image1.jpg"); connection.setRequestMethod("GET"); String contentType = connection.getHeaderField("Content-type"); InputStream responseData = connection.openInputStream(); connection.close(); outputFinal(responseData, contentType); } public synchronized void outputFinal(InputStream result, String contentType) throws SAXException, ParserConfigurationException, IOException { if(contentType.startsWith("text/")) { // bunch of xml save code that works fine } else if(contentType.equals("image/png") || contentType.equals("image/jpeg") || contentType.equals("image/gif")) { // how to save images here? } else { //default } } What I can't find any good documentation on is how one would take the response data and save it to an image stored on the device. Maybe I just overlooked something very obvious. Any help is very appreciated. Thanks

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  • JMS MessageCreator.createMessage() in Grails

    - by Hans Wurst
    Hi there, I am trying to implement jms to my grails application. I have several JMS consumer in a spring based enviroment listining on an ActiveMQ broker. I wrote a simple test commandline client which creates messages and receives them in an request response manner. Here is the snippet that sends a MapMessage in Spring JMS way. This works for me as long I am in my spring world. final String corrID = UUID.randomUUID().toString(); asyncJmsTemplate.send("test.RequestQ", new MessageCreator() { public Message createMessage(Session session) throws JMSException { try { MapMessage msg = session.createMapMessage(); msg.setStringProperty("json", mapper.writeValueAsString(List<of some objects>)); msg.setJMSCorrelationID(corrID); msg.setJMSReplyTo(session.createQueue("test.ReplyQ")); return msg; } catch (JsonGenerationException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (JsonMappingException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } }); BUT when I tried to implement this methods to my grails test app I receive some METHOD_DEF exceptions. Sending simple TextMessages via the jmsTemplate.convertAndSende(Queue, Message) provided by the JMS Plugin works. Can any one help me? Is this a common problem? Cheers Hans

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  • wxPython, Threads, and PostEvent between modules

    - by Sam Starling
    I'm relatively new to wxPython (but not Python itself), so forgive me if I've missed something here. I'm writing a GUI application, which at a very basic level consists of "Start" and "Stop" buttons that start and stop a thread. This thread is an infinite loop, which only ends when the thread is stopped. The loop generates messages, which at the moment are just output using print. The GUI class and the infinite loop (using threading.Thread as a subclass) are held in separate files. What is the best way to get the thread to push an update to something like a TextCtrl in the GUI? I've been playing around with PostEvent and Queue, but without much luck. Here's some bare bones code, with portions removed to keep it concise: main_frame.py import wx from loop import Loop class MainFrame(wx.Frame): def __init__(self, parent, title): # Initialise and show GUI # Add two buttons, btnStart and btnStop # Bind the two buttons to the following two methods self.threads = [] def onStart(self): x = Loop() x.start() self.threads.append(x) def onStop(self): for t in self.threads: t.stop() loop.py class Loop(threading.Thread): def __init__(self): self._stop = threading.Event() def run(self): while not self._stop.isSet(): print datetime.date.today() def stop(self): self._stop.set() I did, at one point, have it working by having the classes in the same file by using wx.lib.newevent.NewEvent() along these lines. If anyone could point me in the right direction, that'd be much appreciated.

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  • Jquery .hide problem

    - by Sergio
    I'm using jquery to show animated MSN like window at the bottom of the page. Jquery code: $(document).ready(function() { $(" .inner").stop().animate({height:'142px'},{queue:false, duration:600}); $(' .close').click(function(event) { $(' .inner').hide(); }); $(' .inner').click(function() { location.replace("somepage.php"); }); }); The CSS: .close {height:14px; z-index:100; position: absolute; margin-left:174px; margin-top:12px; border:1px solid #F00;} .inner {position:absolute;bottom:0;width:201px;height:117px;right: 0; margin-right:10px; float:left; z-index:-1; display:block; cursor:pointer;} The problem that I have with this code is that the close button (showing at the right top corner of .inner DIV) can't fire Jquery .hide function. Why?

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  • EPIPE blocks server

    - by timn
    I have written a single-threaded asynchronous server in C running on Linux: The socket is non-blocking and as for polling, I am using epoll. Benchmarks show that the server performs fine and according to Valgrind, there are no memory leaks or other problems. The only problem is that when a write() command is interrupted (because the client closed the connection), the server will encounter a SIGPIPE. I am doing the interrupted artifically by running the benchmarking utility "siege" with the parameter -b. It does lots of requests in a row which all work perfectly. Now I press CTRL-C and restart the "siege". Sometimes I am lucky and the server does not manage to send the full response because the client's fd is invalid. As expected errno is set to EPIPE. I handle this situation, execute close() on the fd and then free the memory related to the connection. Now the problem is that the server blocks and does not answer properly anymore. Here is the strace output: accept(3, {sa_family=AF_INET, sin_port=htons(50611), sin_addr=inet_addr("127.0.0.1")}, [16]) = 5 fcntl64(5, F_GETFD) = 0 fcntl64(5, F_SETFL, O_RDONLY|O_NONBLOCK) = 0 epoll_ctl(4, EPOLL_CTL_ADD, 5, {EPOLLIN|EPOLLERR|EPOLLHUP|EPOLLET, {u32=158310248, u64=158310248}}) = 0 epoll_wait(4, {{EPOLLIN, {u32=158310248, u64=158310248}}}, 128, -1) = 1 read(5, "GET /user/register HTTP/1.1\r\nHos"..., 4096) = 161 write(5, "HTTP/1.1 200 OK\r\nContent-Type: t"..., 106) = 106 <<<<< write(5, "00001000\r\n", 10) = -1 EPIPE (Broken pipe) <<<<< Why did the previous write() work fine but not this one? --- SIGPIPE (Broken pipe) @ 0 (0) --- As you can see, the client establishes a new connection which consequently is accepted. Then, it's added to the EPOLL queue. epoll_wait() signalises that the client sent data (EPOLLIN). The request is parsed and and a response is composed. Sending the headers works fine but when it comes to the body, write() results in an EPIPE. It is not a bug in "siege" because it blocks any incoming connections, no matter from which client.

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  • using jquery growl with php/mysql

    - by jeansymolanza
    on my database i am planning to create a table storing messages to alert users of anything they need to do. i am looking at using a jQuery growl like notification method but im confused at how i would begin building it. the data would be added into the database using the standard MYSQL insert method from a form but how would i select messages from the database to display using the jQuery growl. would this require the use of ajax? this is the javascript code i have so far, i was wondering how i would implement the php code alongside it so that i can pull out data from my tables to display as notifications: <script type="text/javascript"> // In case you don't have firebug... if (!window.console || !console.firebug) { var names = ["log", "debug", "info", "warn", "error", "assert", "dir", "dirxml", "group", "groupEnd", "time", "timeEnd", "count", "trace", "profile", "profileEnd"]; window.console = {}; for (var i = 0; i < names.length; ++i) window.console[names[i]] = function() {}; } (function($){ $(document).ready(function(){ // This specifies how many messages can be pooled out at any given time. // If there are more notifications raised then the pool, the others are // placed into queue and rendered after the other have disapeared. $.jGrowl.defaults.pool = 5; var i = 1; var y = 1; setInterval( function() { if ( i < 3 ) { $.jGrowl("Message " + i, { sticky: true, log: function() { console.log("Creating message " + i + "..."); }, beforeOpen: function() { console.log("Rendering message " + y + "..."); y++; } }); } i++; } , 1000 ); }); })(jQuery); </script> <p> thanking you in advance and God bless

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  • client-server syncing methodology [theoretical]

    - by Kenneth Ballenegger
    I'm in the progress of building an web-app that syncs with an iOS client. I'm currently tackling trying to figure out how to go about about syncing. I've come up with following two directions: I've got a fairly simple server web-app with a list of items. They are ordered by date modified and as such syncing the order does not matter. One direction I'm considering is to let the client deal with syncing. I've already got an API that lets the client get the data, as well as do certain actions on it, such as update, add or remove single items. I was considering: 1) on each sync asking the server for all items modified since the last successful sync and updating the local records based on what's returned by the server, and 2) building a persistent queue of create / remove / update requests on the client, and keeping them until confirmation by the server. The risk with this approach is that I'm basically asking each side to send changes to the other side, hoping it works smoothly, but risking a diversion at some point. This would probably be more bandwidth-efficient, though. The other direction I was considering was a more traditional model. I would have a "sync" process in which the client would send its whole list to the server (or a subset since last modified sync), the server would update the data on the server (by fixing conflicts by keeping the last modified item, and keeping deleted items with a deleted = 1 field), and the server would return an updated list of items (since last successful sync) which the client would then replace its data with. Thoughts?

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  • Best practices for Java logging from multiple threads?

    - by Jason S
    I want to have a diagnostic log that is produced by several tasks managing data. These tasks may be in multiple threads. Each task needs to write an element (possibly with subelements) to the log; get in and get out quickly. If this were a single-task situation I'd use XMLStreamWriter as it seems like the best match for simplicity/functionality without having to hold a ballooning XML document in memory. But it's not a single-task situation, and I'm not sure how to best make sure this is "threadsafe", where "threadsafe" in this application means that each log element should be written to the log correctly and serially (one after the other and not interleaved in any way). Any suggestions? I have a vague intuition that the way to go is to use a queue of log elements (with each one able to be produced quickly: my application is busy doing real work that's performance-sensitive), and have a separate thread which handles the log elements and sends them to a file so the logging doesn't interrupt the producers. The logging doesn't necessarily have to be XML, but I do want it to be structured and machine-readable. edit: I put "threadsafe" in quotes. Log4j seems to be the obvious choice (new to me but old to the community), why reinvent the wheel...

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  • Why do i get exc bad access in cases when object is not nil?

    - by DixieFlatline
    I have an app that receives remote notifications. My view controller that is shown after push has a tableview. App crashes very randomly (1 in 20 tries) at line setting frame: if (!myTableView) { NSLog(@"self.myTableView is nil"); } myTableView.frame=CGRectMake(0, 70, 320, 376); This only happens when i open the app, then open some other apps and then receive the push notification. I guess it has something to do with memory. I use ARC (ios 5). The strange thing is that nslog is not displayed, so tableview is not nil. Crash log: Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x522d580c Crashed Thread: 0 Thread 0 name: Dispatch queue: com.apple.main-thread Thread 0 Crashed: 0 libobjc.A.dylib 0x352b1f7e objc_msgSend + 22 1 Foundation 0x37dc174c NSKVOPendingNotificationCreate + 216 2 Foundation 0x37dc1652 NSKeyValuePushPendingNotificationPerThread + 62 3 Foundation 0x37db3744 NSKeyValueWillChange + 408 4 Foundation 0x37d8a848 -[NSObject(NSKeyValueObserverNotification) willChangeValueForKey:] + 176 5 Foundation 0x37e0ca14 _NSSetPointValueAndNotify + 76 6 UIKit 0x312af25a -[UIScrollView(Static) _adjustContentOffsetIfNecessary] + 1890 7 UIKit 0x312cca54 -[UIScrollView setFrame:] + 548 8 UIKit 0x312cc802 -[UITableView setFrame:] + 182 9 POViO 0x000913cc -[FeedVC viewWillAppear:] (FeedVC.m:303) Dealloc is not called because it is not logged: - (void)dealloc { NSLog(@"dealloc"); }

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  • delete UITableView row apple addMusic example

    - by Pavan
    Hi, i am trying to add a swipe to delete feature to the addmusic example project (downloaded free from apple) so that i am able able to delete a specific row. Ive added the following code just so that i can enable to delete feature but i dont know how to remove the song from the list which i believe to be the mediaItemCollection and actually deleting it from the userMediaItemCollection which is used to queue the songs to the player. - (void)tableView:(UITableView*)tableView willBeginEditingRowAtIndexPath:(NSIndexPath *)indexPath { } - (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath { // If row is deleted, remove it from the list. if (editingStyle == UITableViewCellEditingStyleDelete) { // delete your data item here // Animate the deletion from the table. [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath]withRowAnimation:UITableViewRowAnimationFade]; } } The swipe to delete feature works nicely, the delete button only appears when swiped, but when i click delete, a SIGBART error occurs, the whole application freezes, (although the musix does continue to play, lol). Can someone please tell me how i can delete the row at that index and how i can delete it from the mediaitemcollection please. When taking that single line of code out: [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath]withRowAnimation:UITableViewRowAnimationFade]; the swipe to delete works, except that it does not delete anything obviously since i havent added any actual delete functionality/coding that needs to be done. All ideas appreciated.

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  • plupload with webpy.

    - by markus
    Hi, i have a problem. I want to upload a file with plupload with the HML5 runtime. This is my html/js code : jQuery(function(){ jQuery("#uploader").pluploadQueue({ // General settings runtimes : 'html5', name : 'file', url : 'http://server.name/addContent', max_file_size : '${maxSize}$_("GB")', }); jQuery('#form_upload_file').submit(function(e) { var uploader = jQuery('#uploader').pluploadQueue(); // Validate number of uploaded files if (uploader.total.uploaded == 0) { // Files in queue upload them first if (uploader.files.length > 0) { // When all files are uploaded submit form uploader.bind('UploadProgress', function() { if (uploader.total.uploaded == uploader.files.length) jQuery('#form_upload_file').submit(); }); uploader.start(); } else alert('You must at least upload one file.'); e.preventDefault(); } }); }); <form id="form_upload_file" action="#" method="POST"> <div id="uploader"></div> <input type="hidden" name="token" value="token" /> <input type="hidden" name="idUser" value="$idUser" /> </form> So, when i click in the button to upload(the submit() method is not called), it does an OPTIONS HTTP request to my server so i don't know what i must do to save the file? this is my webpy code : def OPTIONS(self): web.header('Content-type', 'text/plain: charset=utf-8') web.header('Cache-Control', 'no-store, no-cache, must-revalidate') web.header('Cache-Control', 'post-check=0, pre-check=0', False) web.header('Pragma', 'no-cache') def POST(self): input = web.input(_unicode=False, file={})#on récupère les input self.copy(input.file.file) etc. any idea ? thanks.

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  • Crash on iOS when system purges memory and closes a UIViewController

    - by Amiramix
    My application is crashing when one of the views is purged from memory because of low-memory condition. At least this is what I understand from the crashlog. It happens on numerous screens but only when opening a Facebook dialog (using the Facebook SDK). Basically, looks like the system sometimes runs out of memory when we need to present a Facebook dialog (e.g. to let user post something on the Facebook timeline). Date/Time: 2012-03-14 19:47:33.819 +0000 OS Version: iPhone OS 5.1 (9B176) Report Version: 104 Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x30000008 Crashed Thread: 0 Thread 0 name: Dispatch queue: com.apple.main-thread Thread 0 Crashed: 0 libobjc.A.dylib 0x30f2bf78 objc_msgSend + 16 1 MyApp 0x00003c0e -LTBaseViewController viewDidUnload (LTBaseViewController.m:145) 2 MyApp 0x00004ea2 -LTBaseTableViewController viewDidUnload (LTBaseTableViewController.m:90) 3 UIKit 0x33766bd8 -[UIViewController unloadViewForced:] + 244 4 UIKit 0x338ae492 -[UIViewController purgeMemoryForReason:] + 58 5 Foundation 0x3071a4f8 __57-NSNotificationCenter addObserver:selector:name:object:_block_invoke_0 + 12 6 CoreFoundation 0x30e95540 ___CFXNotificationPost_block_invoke_0 + 64 7 CoreFoundation 0x30e21090 _CFXNotificationPost + 1400 8 Foundation 0x3068e3e4 -NSNotificationCenter postNotificationName:object:userInfo: + 60 9 Foundation 0x3068fc14 -NSNotificationCenter postNotificationName:object: + 24 10 UIKit 0x3387926a -UIApplication _performMemoryWarning + 74 11 UIKit 0x33879364 -UIApplication _receivedMemoryNotification + 168 12 libdispatch.dylib 0x36a12252 _dispatch_source_invoke + 510 13 libdispatch.dylib 0x36a0fb1e _dispatch_queue_invoke$VARIANT$up + 42 14 libdispatch.dylib 0x36a0fe64 _dispatch_main_queue_callback_4CF$VARIANT$up + 152 15 CoreFoundation 0x30e9c2a6 __CFRunLoopRun + 1262 16 CoreFoundation 0x30e1f49e CFRunLoopRunSpecific + 294 17 CoreFoundation 0x30e1f366 CFRunLoopRunInMode + 98 18 GraphicsServices 0x33fb6432 GSEventRunModal + 130 19 UIKit 0x336f5e76 UIApplicationMain + 1074 20 MyApp 0x00004818 main (main.m:16) 21 MyApp 0x000023b4 0x1000 + 5044 I checked and there are almost no memory leaks, e.g. when testing the app for an hour the total memory leaked was around 2-3Kb caused by some string-copying libraries. So I don't believe this is caused by the application. I guess that when the phone is not restarted for some time there are applications running in the background and when using Facebook SDK the memory becomes a problem and the system tries to recover the memory from random applications, including my application. My question is, how can I prevent this crash from happening? How should I handle unloadViewForced on a view controller to make the app more robust in low-memory conditions? And lastly, am I right that this crashlog suggests the crash occurred because the system tried to free memory and my application didn't handle it properly? Any help greatly appreciated.

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  • best way to switch between secure and unsecure connection without bugging the user

    - by Brian Lang
    The problem I am trying to tackle is simple. I have two pages - the first is a registration page, I take in a few fields from the user, once they submit it takes them to another page that processes the data, stores it to a database, and if successful, gives a confirmation message. Here is my issue - the data from the user is sensitive - as in, I'm using an https connection to ensure no eavesdropping. After that is sent to the database, I'd like on the confirmation page to do some nifty things like Google Maps navigation (this is for a time reservation application). The problem is by using the Google Maps api, I'd be linking to items through a unsecure source, which in turn prompts the user with a nasty warning message. I've browsed around, Google has an alternative to enterprise clients, but it costs $10,000 a year. What I am hoping is to find a workaround - use a secure connection to take in the data, and after it is processed, bring them to a page that isn't secure and allows me to utilize the Google Maps API. If any of you have a Netflix account you can see exactly what I would like to do when you sign-in, it is a secure page, which then takes you to your account / queue, on an unsecure page. Any suggestions? Thanks!

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  • Throttling outbound API calls generated by a Rails app

    - by Sharpie
    I am not a professional web developer, but I like to wrench on websites as a hobby. Recently, I have been playing with developing a Rails app as a project to help me learn the framework. The goal of my toy app is to harvest data from another service through their API and make it available for me to query using a search function. However, the service I want to pull data from imposes a rate limit on the number of API calls that may be executed per minute. I plan on having my app run a daily update which may generate a burst of API calls that far exceeds the limit provided by the external service. I wish to respect the performance of the external site and so would like to throttle the rate at which my app executes the calls. I have done a little bit of searching and the overwhelming amount of tutorial material and pre-built libraries I have found cover throttling inbound API calls to a web app and I can find little discussion of controlling the flow of outbound calls. Being both an amateur web developer and a rails newbie, it is entirely possible that I have been executing the wrong searches in the wrong places. Therefore my questions are: Is there a nice website out there aggregating Rails tutorials that has material related to throttling outbound API requests? Are there any ruby gems or other libraries that would help me throttle the requests? I have some ideas of how I might go about writing a throttling system using a queue-based worker like DelayedJob or Resque to manage the API calls, but I would rather spend my weekends building the rest of the site if there is a good pre-built solution out there already.

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  • Threads, Sockets, and Designing Low-Latency, High Concurrency Servers

    - by lazyconfabulator
    I've been thinking a lot lately about low-latency, high concurrency servers. Specifically, http servers. http servers (fast ones, anyway) can serve thousands of users simultaneously, with very little latency. So how do they do it? As near as I can tell, they all use events. Cherokee and Lighttpd use libevent. Nginx uses it's own event library performing much the same function of libevent, that is, picking a platform optimal strategy for polling events (like kqueue on *bsd, epoll on linux, /dev/poll on Solaris, etc). They all also seem to employ a strategy of multiprocess or multithread once the connection is made - using worker threads to handle the more cpu intensive tasks while another thread continues to listen and handle connections (via events). This is the extent of my understanding and ability to grok the thousand line sources of these applications. What I really want are finer details about how this all works. In examples of using events I've seen (and written) the events are handling both input and output. To this end, do the workers employ some sort of input/output queue to the event handling thread? Or are these worker threads handling their own input and output? I imagine a fixed amount of worker threads are spawned, and connections are lined up and served on demand, but how does the event thread feed these connections to the workers? I've read about FIFO queues and circular buffers, but I've yet to see any implementations to work from. Are there any? Do any use compare-and-swap instructions to avoid locking or is locking less detrimental to event polling than I think? Or have I misread the design entirely? Ultimately, I'd like to take enough away to improve some of my own event-driven network services. Bonus points to anyone providing solid implementation details (especially for stuff like low-latency queues) in C, as that's the language my network services are written in.

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  • "Work stealing" vs. "Work shrugging"?

    - by John
    Why is it that I can find lots of information on "work stealing" and nothing on "work shrugging" as a dynamic load-balancing strategy? By "work-shrugging" I mean busy processors pushing excessive work towards less loaded neighbours rather than idle processors pulling work from busy neighbours ("work-stealing"). I think the general scalability should be the same for both strategies. However I believe that it is much more efficient for busy processors to wake idle processors if and when there is definitely work for them to do than having idle processors spinning or waking periodically to speculatively poll all neighbours for possible work. Anyway a quick google didn't show up anything under the heading of "Work Shrugging" or similar so any pointers to prior-art and the jargon for this strategy would be welcome. Clarification/Confession In more detail:- By "Work Shrugging" I actually envisage the work submitting processor (which may or may not be the target processor) being responsible for looking around the immediate locality of the preferred target processor (based on data/code locality) to decide if a near neighbour should be given the new work instead because they don't have as much work to do. I am talking about an atomic read of the immediate (typically 2 to 4) neighbours' estimated q length here. I do not think this is any more coupling than implied by the thieves polling & stealing from their neighbours - just much less often - or rather - only when it makes economic sense to do so. (I am assuming "lock-free, almost wait-free" queue structures in both strategies). Thanks.

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  • show UIAlertView when In app purchase is in progress

    - by edie
    Hi... I've added an UIAlertView that has UIActivityIndicatior as a subview on my application. This alertView only show when the purchase is in progress. I've put my alert view in this way in my StoreObserver: - (void)paymentQueue:(SKPaymentQueue *)queue updatedTransactions:(NSArray *)transactions { for (SKPaymentTransaction *transaction in transactions) { switch (transaction.transactionState) { case SKPaymentTransactionStatePurchasing: [self stillPurchasing]; // this creates an alertView and shows break; case SKPaymentTransactionStatePurchased: [self completeTransaction:transaction]; break; case SKPaymentTransactionStateFailed: [self failedTransaction:transaction]; break; case SKPaymentTransactionStateRestored: [self restoreTransaction:transaction]; break; default: break; } } } - (void) stillPurchasing { UIAlertView *alert = [[UIAlertView alloc]initWithTitle: @"In App Purchase" message: @"Processing your purchase..." delegate: nil cancelButtonTitle: nil otherButtonTitles: nil]; self.alertView = alert; [alert release]; UIActivityIndicatorView *ind = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle: UIActivityIndicatorViewStyleWhiteLarge]; self.indicator = ind; [ind release]; [self.indicator startAnimating]; [self.alertView addSubview: self.indicator]; [self.alertView show]; } When I tap my the buy button this UIAlertView shows together with my UIActivityIndicator.. But when the transaction completes the alertView still on the top of the view and the Indicator was the only one that was removed. My question was how should I release the alertView? Or where/When should I release it. I've added these command to release my alertView and Indicator on these cases: case SKPaymentTransactionStatePurchased: case SKPaymentTransactionStateFailed: case SKPaymentTransactionStateRestored: [self.indicator stopAnimating]; [self.indicator removeFromSuperview]; [self.alertView release]; [self.indicator release]; I've only added the alertView to show that the purchasing was still in progress. Any suggestion to create any feedback to users will be thankful for me.. Thanks

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  • Is it possible to have anonymous purchases with ubercart without the creation of a new user account?

    - by DKinzer
    I would like to be able to have anonymous users purchase a product but not have a new account created when they purchase it. Unfortunately the creation of a new user seems to be very tightly integrated into ubercart's ordering system. And, because the order module is part of the ubercart core, it's behavior cannot be overridden easily. One possibility for overriding is the creation of a new user account by supplying ubercart with an bogus anonymous account: hook into hook_form_alter at $form_id == 'uc_cart_checkout_review_form' because this is where ubercart first associates the $order to an uid. Add our submit function to the queue: //Find out if the user is anonymous: global $user; if ($user->uid == 0 ) { //Load a previously created anonymous user account $anonymous_user = mymodule_get_anonymous_user(); //create the order and assign our anonymous_user_id to it $order = uc_order_load($_SESSION['cart_order']); $order->uid = $anonymous_user->uid; uc_order_save($order); //Assign the global user our anonymous user uid $user->uid = $anonymous_user->uid; } But what I really need is to be able to have an anonymous purchase without being forced to create a new account, this solution does not work for me. Apart from which, using this technique will automatically login the anonymous_user into our bogus_anonymous_user account. Which is definitely something I don't want. Is there a better non-duct-tape way around the creation of a new user account for anonymous purchases in ubercart?. AND FYI - at this point I'm kind of stuck with ubercart so I cannot use something else. Thanks! D

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  • Windows Messages Bizarreness

    - by jameszhao00
    Probably just a gross oversight of some sort, but I'm not receiving any WM_SIZE messages in the message loop. However, I do receive them in the WndProc. I thought the windows loop gave messages out to WndProc? LRESULT CALLBACK WndProc( HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam ) { switch(message) { // this message is read when the window is closed case WM_DESTROY: { // close the application entirely PostQuitMessage(0); return 0; } break; case WM_SIZE: return 0; break; } printf("wndproc - %i\n", message); // Handle any messages the switch statement didn't return DefWindowProc (hWnd, message, wParam, lParam); } ... and now the message loop... while(TRUE) { // Check to see if any messages are waiting in the queue if(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { // translate keystroke messages into the right format TranslateMessage(&msg); // send the message to the WindowProc function DispatchMessage(&msg); // check to see if it's time to quit if(msg.message == WM_QUIT) { break; } if(msg.message == WM_SIZING) { printf("loop - resizing...\n"); } } else { //do other stuff } }

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  • Proving that the distance values extracted in Dijkstra's algorithm is non-decreasing?

    - by Gail
    I'm reviewing my old algorithms notes and have come across this proof. It was from an assignment I had and I got it correct, but I feel that the proof certainly lacks. The question is to prove that the distance values taken from the priority queue in Dijkstra's algorithm is a non-decreasing sequence. My proof goes as follows: Proof by contradiction. Fist, assume that we pull a vertex from Q with d-value 'i'. Next time, we pull a vertex with d-value 'j'. When we pulled i, we have finalised our d-value and computed the shortest-path from the start vertex, s, to i. Since we have positive edge weights, it is impossible for our d-values to shrink as we add vertices to our path. If after pulling i from Q, we pull j with a smaller d-value, we may not have a shortest path to i, since we may be able to reach i through j. However, we have already computed the shortest path to i. We did not check a possible path. We no longer have a guaranteed path. Contradiction.

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  • How to recursive rake? -- or suitable alternatives

    - by TerryP
    I want my projects top level Rakefile to build things using rakefiles deeper in the tree; i.e. the top level rakefile says how to build the project (big picture) and the lower level ones build a specific module (local picture). There is of course a shared set of configuration for the minute details of doing that whenever it can be shared between tasks: so it is mostly about keeping the descriptions of what needs building, as close to the sources being built. E.g. /Source/Module/code.foo and cie should be built using the instructions in /Source/Module/Rakefile; and /Rakefile understands the dependencies between modules. I don't care if it uses multiple rake processes (ala recursive make), or just creates separate build environments. Either way it should be self-containable enough to be processed by a queue: so that non-dependent modules could be built simultaneously. The problem is, how the heck do you actually do something like that with Rake!? I haven't been able to find anything meaningful on the Internet, nor in the documentation. I tried creating a new Rake::Application object and setting it up, but whatever methods I try invoking, only exceptions or "Don't know how to build task ':default'" errors get thrown. (Yes, all rakefiles have a :default). Obviously one could just execute 'rake' in a sub directory for a :modulename task, but that would ditch the options given to the top level; e.g. think of $(MAKE) and $(MAKEFLAGS). Anyone have a clue on how to properly do something like a recursive rake?

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  • Advice on designing and building distributed application to track vehicles

    - by dario-g
    I'm working on application for tracking vehicles. There will be about 10k or more vehicles. Each will be sending ~250bytes in each minute. Data contains gps location and everything from CAN Bus (every data that we can read from vehicle computer and dashboard). Data are sent by GSM/GPRS (using UDP protocol). Estimated rows with this data per day is ~2000k. I see there 3 main blocks. 1. Multithreaded Socket Server (MSS) - I have it. MSS stores received data to the queue (using NServiceBus). 2. Rule Processor Server (RPS) - this is core of this system. This block is responsible for parsing received data, storing in the database, processing rules, sending messages to Notifier Server (this will be sending e-mails/sms texts). Rule example. As I said between received bytes there will be information about current speed. When speed will be above 120 then: show alert in web application for specified users, send e-mail, send sms text. (There can be more than one instance of RPS). 3. Web application - allows reporting and defining rules by users, monitoring alerts, etc. I'm looking for advice how to design communication between RPS and Web application. Some questions: - Should Web application and RPS have separated databases or one central database will be enough? I have one domain model in web application. If there will be one central database then can I use the same model (objects) on RPS? So, how to send changed rules to RPS? I try to decouple this blocks as much as possible. I'm planning to create different instance of application for each client (each client will have separated database). One client will be have 10k vehicles, others only 100 vehicles.

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  • Radix Sort in Python [on hold]

    - by Steven Ramsey
    I could use some help. How would you write a program in python that implements a radix sort? Here is some info: A radix sort for base 10 integers is a based on sorting punch cards, but it turns out the sort is very ecient. The sort utilizes a main bin and 10 digit bins. Each bin acts like a queue and maintains its values in the order they arrive. The algorithm begins by placing each number in the main bin. Then it considers the ones digit for each value. The rst value is removed and placed in the digit bin corresponding to the ones digit. For example, 534 is placed in digit bin 4 and 662 is placed in the digit bin 2. Once all the values in the main bin are placed in the corresponding digit bin for ones, the values are collected from bin 0 to bin 9 (in that order) and placed back in the main bin. The process continues with the tens digit, the hundreds, and so on. After the last digit is processed, the main bin contains the values in order. Use randint, found in random, to create random integers from 1 to 100000. Use a list comphrension to create a list of varying sizes (10, 100, 1000, 10000, etc.). To use indexing to access the digits rst convert the integer to a string. For this sort to work, all numbers must have the same number of digits. To zero pad integers with leading zeros, use the string method str.zfill(). Once main bin is sorted, convert the strings back to integers. I'm not sure how to start this, Any help is appreciated. Thank you.

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