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  • VS2010 express beta2 - no add reference dialog, no open file/project dialogs

    - by David
    Just installed VS2010 express for Windows Phone last night. Install went smoothly. It creates a project, compiles, and deploys the app to the emulator. Here's the problem: When I try to "Add Reference" through the Project menu, I do not get the Add Reference dialog box. Same thing if I right click References in the solution explorer and click Add Reference. That's not all. "File...Open" and "File...Open Project" also fail to throw up an open file dialog box. When attempting any of these actions, the IDE quickly loses and regains focus. Even pressing a keyboard shortcut (Ctrl+O) causes the IDE to quickly lose and regain focus, but no open file dialog box appears. This is what I have tried, not particularly in this order: 1. Turned off UAC 2. Monitored file and registry access using Process Monitor during a File...Open operation. File activity showed mostly "SUCCESS" with a few "FAST IO DISALLOWED" and a few "INVALID DEVICE REQUEST" results. Registry activity showed mostly "SUCCESS" with some "NAME NOT FOUND" and a few "BUFFER OVERFLOW" results. 3. Created a new, clean Windows account to run the IDE from 4. Forced a test project to add a reference to "System.Xml.Linq" by editing the ".csproj" project file. Project failed to load in the IDE. I don't have these problems at all on 2 other Windows 7 computers with VS2010 C# express beta 2 installed. One machine is 32bit and the other 64bit, both Home Premium edition. My system: Windows 7 Home Premium, 64bit Other Visual Studio products installed: VS2008 C# express, VS2008 C++ express One other thing to note: Several months ago I installed the non-phone distribution of VS2010 C# express beta 2, and I had the same exact problems. Back then I chalked it up to being beta and went back to VS2008 C# express, where I do not have these issues.

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  • Which articles I've should read before starting to make my custom drawn winforms app?

    - by Dmitriy Matveev
    Hello! I'm currently developing a windows forms application with a lot of user controls. Some of them are just custom drawn buttons or panels and some of them are a compositions of these buttons and panels inside of FlowLayoutPanels and TableLayoutPanels. And the window itself is also custom drawn. I don't have much experience in winforms development, but I've made a proper decomposition of proposed design into user controls and implementation is already almost finished. I've already solved many arisen problems during development by the help of the google, msdn, SO and several dirty hacks (when nothing were helping) and still experiencing some of them. There are a lot of gaps in my knowledge base, since I don't know answers to many questions like: When I should use things like double buffer, suspended layout, suspended redraw ? What should I do with the controls which shouldn't be visible at some moment ? Common performance pitfalls (I think I've fallen in in several ones) ? So I think there should be some great articles which can give some knowledge enough to avoid most common problems and improve performance and maintainability of my application. Maybe some of you can recommend a few?

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  • Form not updating usercontrol

    - by user328259
    From the post "Growing user control not updating"... Using C#, .Net 2.0 in a Windows environment. UserControl1 - draws cells to a bitmap buffer dependent upon NumberOfCells property UserControl2 - panel contains UserControl1 which displays vertical scroll when necessary; also contains NumberOfCells which sets UserControl1's NumberOfCells. Formf1 - contains NumericUpDown controls (just increments) which updates the UserControl2 - suppose to! When I increment the control on the form by say 20, UserControl1 adds the necessary cells, UserControl2 displays the vertical scroll bar accordingly, BUT the form does not 'redraw' to the updated/correct image!! Meaning, after I increment by 20, cells are added, vertical scrool bar added... but the image shown is just everything else expanding. I reset the control to scoll to the very TOP and the scrolling works, but the image is still staic... UNTIL I resize my form, more specifically, when I change it from maximize to window or vice versa!!! What can I do to 'reset/redraw' the correct image???? Thank you in advance. Lawrence

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  • Deleting a non-owned dynamic array through a pointer

    - by ayanzo
    Hello all, I'm relatively novice when it comes to C++ as I was weened on Java for much of my undergraduate curriculum (tis a shame). Memory management has been a hassle, but I've purchased a number books on ansi C and C++. I've poked around the related questions, but couldn't find one that matched this particular criteria. Maybe it's so obvious nobody mentions it? This question has been bugging me, but I feel as if there's a conceptual point i'm not utilizing. Suppose: char original[56]; cstr[0] = 'a'; cstr[1] = 'b'; cstr[2] = 'c'; cstr[3] = 'd'; cstr[4] = 'e'; cstr[5] = '\0'; char *shaved = shavecstr(cstr); delete[] cstrn; where char* shavecstr(char* cstr) { size_t len = strlen(cstr); char* ncstr = new char[len]; strcpy(ncstr,cstr); return ncstr; } In that the whole point is to have 'original' be a buffer that fills with characters and routinely has its copy shaved and used elsewhere. To prevent leaks, I want to free up the memory held by 'shaved' to be used again after it passes through some arguments. There is probably a good reason for why this is restricted, but there should be some way to free the memory as by this configuration, there is no way to access the original owner (pointer) of the data.

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  • C++ boost.asio server and client connection undersanding

    - by Edgar Buchvalov
    i started learning boost.asio and i have some problems with undersanding tcp connections. There is example from official boost site: #include <ctime> #include <iostream> #include <string> #include <boost/asio.hpp> using boost::asio::ip::tcp; std::string make_daytime_string() { using namespace std; // For time_t, time and ctime; time_t now = time(0); return ctime(&now); } int main() { try { boost::asio::io_service io_service; tcp::acceptor acceptor(io_service, tcp::endpoint(tcp::v4(), 13)); for (;;) { tcp::socket socket(io_service); acceptor.accept(socket); std::string message = make_daytime_string(); boost::system::error_code ignored_error; boost::asio::write(socket, boost::asio::buffer(message), boost::asio::transfer_all(), ignored_error); } } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } there is question, why if i want to connet to this server via client i have t write: boost::asio::io_service io_service; tcp::resolver resolver(io_service); tcp::resolver::query query(host_ip, "daytime"); //why daytime? tcp::resolver::iterator endpoint_iterator = resolver.resolve(query); tcp::resolver::iterator end; why daytime?, what it meant and where it is inicialized in server, or i just doesn't missed somefing? there is full client code : www.boost.org/doc/libs/1_39_0/doc/html/boost_asio/tutorial/tutdaytime1.html thanks for explanation in advance

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  • Android: Streaming audio over TCP Sockets

    - by user299988
    Hi, For my app, I need to record audio from MIC on an Android phone, and send it over TCP to the other android phone, where it needs to be played. I am using AudioRecord and AudioTrack class. This works great with a file - write audio to the file using DataOutputStream, and read from it using DataInputStream. However, if I obtain the same stream from a socket instead of a File, and try writing to it, I get an exception. I am at a loss to understand what could possibly be going wrong. Any help would be greatly appreciated. EDIT: The problem is same even if I try with larger buffer sizes (65535 bytes, 160000 bytes). This is the code: Recorder: int bufferSize = AudioRecord.getMinBufferSize(11025, , AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT); AudioRecord recordInstance = new AudioRecord(MediaRecorder.AudioSource.MIC, 11025, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT, bufferSize); byte[] tempBuffer = new byte[bufferSize]; recordInstance.startRecording(); while (/*isRecording*/) { bufferRead = recordInstance.read(tempBuffer, 0, bufferSize); dataOutputStreamInstance.write(tempBuffer); } The DataOutputStream above is obtained as: BufferedOutputStream buff = new BufferedOutputStream(out1); //out1 is the socket's outputStream DataOutputStream dataOutputStreamInstance = new DataOutputStream (buff); Could you please have a look, and let me know what is it that I could be doing wrong here? Thanks,

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  • Is there a way to make changes to toggles in my .emacs file apply without re-starting Emacs?

    - by Vivi
    I want to be able to make the changes to my .emacs file without having to reload Emacs. I found three questions which sort of answer what I am asking (you can find them here, here and here), but the problem is that the change I have just made is to a toggle, and as the comments to two of the answers (a1, a2) to those questions explain, the solutions given there (such as M-x reload-file or M-x eval-buffer) don't apply to toggles. I imagine there is a way of toggling the variable again with a command, but if there is a way to reload the whole .emacs and have the all the toggles re-evaluated without having to specify them, I would prefer. In any case, I would also appreciate if someone told me how to toggle the value of a variable so that if I just changed one toggle I can do it with a command rather than re-start Emacs just for that (I am new to Emacs). I don't know how useful this information is, but the change I applied was the following (which I got from this answer to another question): (setq skeleton-pair t) (setq skeleton-pair-on-word t) (global-set-key (kbd "[") 'skeleton-pair-insert-maybe) (global-set-key (kbd "(") 'skeleton-pair-insert-maybe) (global-set-key (kbd "{") 'skeleton-pair-insert-maybe) (global-set-key (kbd "<") 'skeleton-pair-insert-maybe) Edit: I included the above in .emacs and reloaded Emacs, so that the changes took effect. Then I commented all of it out and tried M-x load-file. This doesn't work. The suggestion below (C-x C-e by PP works if I am using it to evaluate the toggle first time, but not when I want to undo it). I would like something that would evaluate the commenting out, if such thing exists... Thanks :)

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  • Optimizing quality for available bandwidth in Flash/RTMFP

    - by Artem M.
    I'm developing a simple one-on-one P2P video chat using ActionScript, and I'd like to ensure the best video quality for the peers given their bandwidth. This means: Setting the best quality given the available bandwidth when the chat starts Responding to network congestions during chat by decreasing the quality. The task is similar to dynamic stream switching, but P2P has its specifics that make dynamic streaming approaches not work. For example, the maxBytesPerSecond metric monitored in dynamic stream switching is pretty useless in P2P where the receiving NetStream's buffer size is set to 0 to minimize latency. So far, it looks like the most reliable QoS metric for P2P is SRTT. In my simulated tests on a local network, a bandwidth congestion makes it shot up to 500 ms and more when there's a bandwidth limit introduced. However, it gives no hint as to how best adjust the value for bandwidth in Camera.setQuality(0, bandwidth) to respond to the congestion. I've done lots of experiments, and I still don't see a clear and simple solution to the problem. I'm also wondering how this issue is addressed (if at all) in other RTMFP chat solutions.

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  • How to get user input before saving a file in Sublime Text

    - by EddieJessup
    I'm making a plugin in Sublime Text that prompts the user for a password to encrypt a file before it's saved. There's a hook in the API that's executed before a save is executed, so my naïve implementation is: class TranscryptEventListener(sublime_plugin.EventListener): def on_pre_save(self, view): # If document is set to encode on save if view.settings().get('ON_SAVE'): self.view = view # Prompt user for password message = "Create a Password:" view.window().show_input_panel(message, "", self.on_done, None, None) def on_done(self, password): self.view.run_command("encode", {password": password}) The problem with this is, by the time the input panel appears for the user to enter their password, the document has already been saved (despite the trigger being 'on_pre_save'). Then once the user hits enter, the document is encrypted fine, but the situation is that there's a saved plaintext file, and a modified buffer filled with the encrypted text. So I need to make Sublime Text wait until the user's input the password before carrying out the save. Is there a way to do this? At the moment I'm just manually re-saving once the encryption has been done: def on_pre_save(self, view, encode=False): if view.settings().get('ON_SAVE') and not view.settings().get('ENCODED'): self.view = view message = "Create a Password:" view.window().show_input_panel(message, "", self.on_done, None, None) def on_done(self, password): self.view.run_command("encode", {password": password}) self.view.settings().set('ENCODED', True) self.view.run_command('save') self.view.settings().set('ENCODED', False) but this is messy and if the user cancels the encryption then the plaintext file gets saved, which isn't ideal. Any thoughts? Edit: I think I could do it cleanly by overriding the default save command. I hoped to do this by using the on_text_command or on_window_command triggers, but it seems that the save command doesn't trigger either of these (maybe it's an application command? But there's no on_application_command). Is there just no way to override the save function?

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  • Can any linux API or tool watch for any change in any folder below e.g. /SharedRoot or do I have to

    - by Simon B.
    I have a folder with ~10 000 subfolders. Can any linux API or tool watch for any change in any folder below e.g. /SharedRoot or do I have to setup inotify for each folder? (i.e. I loose if I want to do this for 10k+ folders). I guess yes, since I've already seen examples of this inefficient method, for instance http://twistedmatrix.com/trac/browser/trunk/twisted/internet/inotify.py?rev=28866#L345 My problem: I need to keep folders time-sorted with most recently active "project" up top. When a file changes, each folder above that file should update its last-modified timestamp to match the file. Delays are ok. Opening a file (typically MS Excel) and closing again, its file date can jump up and then down again. For this reason I need to wait until after a file is closed, then queue the folder of that file for checking, and only a while later do I go and look for the newest file in its folder, since the filedate of the triggering file could already be back-dated to its original timestamp by Excel or similar programs. Also in case several files from same folder are used/created, it makes sense to buffer timestamping of that folders' parents to at least get a bunch of updates collapsed into one delayed update. I'm looking for a linux solution. I have some code that can be run on a windows server, most of the queing functionality is here: http://github.com/sesam/FolderdateFollowsFiles/blob/master/FolderdateFollowsFiles/Follower.vb Available API:s The relative of inotify on windows, ReadDirectoryChangesW, can watch a folder and its whole subtree; see bWatchSubtree on http://msdn.microsoft.com/en-us/library/aa365465(VS.85).aspx Samba? Patching samba source is a possibility, but perhaps there are already hooks available? Other possibilities, like client side (various windows versions) and spying on file activities in order to update folders recursively?

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  • RSA_sign and RSACryptoProvider.VerifySignature

    - by Miky D
    I'm trying to get up to speed on how to get some code that uses OpenSSL for cryptography, to play nice with another program that I'm writing in C#, using the Microsoft cryptography providers available in .NET. More to the point, I'm trying to have the C# program verify an RSA message signature generated by the OpenSSL code. The code that generates the signature looks something like this: // Code in C, using the OpenSSL RSA implementation char msgToSign[] = "Hello World"; // the message to be signed char signature[RSA_size(rsa)]; // buffer that will hold signature int slen = 0; // will contain signature size // rsa is an OpenSSL RSA context, that's loaded with the public/private key pair memset(signature, 0, sizeof(signature)); RSA_sign(NID_sha1 , (unsigned char*)msgToSign , strlen(msgToSign) , signature , &slen , rsa); // now signature contains the message signature // and can be verified using the RSA_verify counterpart // .. I would like to verify the signature in C# In C#, I would do the following: import the other side's public key into an RSACryptoServiceProvider object receive the message and it's signature try to verify the signature I've got the first two parts working (I've verified that the public key is loading properly because I managed to send an RSA encrypted text from the C# code to the OpenSSL code in C and successfully have it decrypted) In order to verify the signature in C#, I've tried using the: VerifySignature method of the RSACryptoServiceProvider but that didn't work. And digging around the internet I was only able to find some vague information pointing out that .NET uses a different method for generating the signature than OpenSSL does. So, does anybody know how to accomplish this?

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  • Get_user running at kernel mode returns error

    - by Fangkai Yang
    Hi, all, I have a problem with get_user() macro. What I did is as follows: I run the following program int main() { int a = 20; printf("address of a: %p", &a); sleep(200); return 0; } When the program runs, it outputs the address of a, say, 0xbff91914. Then I pass this address to a module running in Kernel Mode that retrieves the contents at this address (at the time when I did this, I also made sure the process didn't terminate, because I put it to sleep for 200 seconds... ): The address is firstly sent as a string, and I cast them into pointer type. int * ptr = (int*)simple_strtol(buffer, NULL,16); printk("address: %p",ptr); // I use this line to make sure the cast is correct. When running, it outputs bff91914, as expected. int val = 0; int res; res= get_user(val, (int*) ptr); However, res is always not 0, meaning that get_user returns error. I am wondering what is the problem.... Thank you!! -- Fangkai

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  • Serial: write() throttling?

    - by damian
    Hi everyone, I'm working on a project sending serial data to control animation of LED lights, which need to stay in sync with a sound engine. There seems to be a large serial write buffer (OSX (POSIX) + FTDI chipset usb serial device), so without manually restricting the transmission rate, the animation system can get several seconds ahead of the serial transmission. Currently I'm manually restricting the serial write speed to the baudrate (8N1 = 10 bytes serial frame per 8 bytes data, 19200 bps serial - 1920 bytes per second max), but I am having a problem with the sound drifting out of sync over time - it starts fine, but after 10 minutes there's a noticeable (100ms+) lag between the sound and the lights. This is the code that's restricting the serial write speed (called once per animation frame, 'elapsed' is the duration of the current frame, 'baudrate' is the bps (19200)): void BufferedSerial::update( float elapsed ) { baud_timer += elapsed; if ( bytes_written > 1024 ) { // maintain baudrate float time_should_have_taken = (float(bytes_written)*10)/float(baudrate); float time_actually_took = baud_timer; // sleep if we have > 20ms lag between serial transmit and our write calls if ( time_should_have_taken-time_actually_took > 0.02f ) { float sleep_time = time_should_have_taken - time_actually_took; int sleep_time_us = sleep_time*1000.0f*1000.0f; //printf("BufferedSerial::update sleeping %i ms\n", sleep_time_us/1000 ); delayUs( sleep_time_us ); // subtract 128 bytes bytes_written -= 128; // subtract the time it should have taken to write 128 bytes baud_timer -= (float(128)*10)/float(baudrate); } } } Clearly there's something wrong, somewhere. A much better approach would be to be able to determine the number of bytes currently in the transmit queue, and try and keep that below a fixed threshold. Any advice appreciated.

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  • How can i zip files in Java and not include files paths

    - by Ignacio
    For example, i want to zip a file stored in /Users/me/Desktop/image.jpg I maded this method: public static Boolean generateZipFile(ArrayList<String> sourcesFilenames, String destinationDir, String zipFilename){ // Create a buffer for reading the files byte[] buf = new byte[1024]; try { // VER SI HAY QUE CREAR EL ROOT PATH boolean result = (new File(destinationDir)).mkdirs(); String zipFullFilename = destinationDir + "/" + zipFilename ; System.out.println(result); // Create the ZIP file ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFullFilename)); // Compress the files for (String filename: sourcesFilenames) { FileInputStream in = new FileInputStream(filename); // Add ZIP entry to output stream. out.putNextEntry(new ZipEntry(filename)); // Transfer bytes from the file to the ZIP file int len; while ((len = in.read(buf)) > 0) { out.write(buf, 0, len); } // Complete the entry out.closeEntry(); in.close(); } // Complete the ZIP file out.close(); return true; } catch (IOException e) { return false; } } But when i extract the file, the unzipped files have the full path. I don't want the full path of each file in the zip i only want the filename. How can i made this?

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  • Sending jpegs by tcp socket...sometimes incomplete.

    - by Guy
    Vb.net Hi I've been working on a project for months now (vb 2008 express). There is one final problem which I can't solve. I need to send images to a client from a 'server'(listener). The code below works most of the time but sometimes the image is incomplete. I believe this might be something to do with the tcp packet sizes varying, maybe limited by how busy it is out there on the net. I have seen examples of code that splits the image into chunks and sends them out, but I can't get them to work maybe because I'm using a different vb version. The pictures to be sent are small 20k max. Any working code examples would be wonderful. I have been experimenting and failing with this final hurdle for weeks. Thanks in anticipation. Client----- Sub GetPic() '------- Connect to Server ClientSocket = New Socket(AddressFamily.InterNetwork, SocketType.Stream, _ ProtocolType.Tcp) ClientSocket.Connect(Epoint) '------- Send Picture Request Dim Bytes() As Byte = System.Text.ASCIIEncoding.ASCII.GetBytes("Send Picture") ClientSocket.Send(Bytes, Bytes.Length, SocketFlags.None) '------- Receive Response Dim RecvBuffer(20000) As Byte Dim Numbytes As Integer Numbytes = ClientSocket.Receive(RecvBuffer) Dim Darray(Numbytes) As Byte Buffer.BlockCopy(RecvBuffer, 0, Darray, 0, Numbytes) '------- Close Connection ClientSocket.Shutdown(SocketShutdown.Both) ClientSocket.Close() '------- Dim MStrm = New MemoryStream(Darray) Picture = Image.FromStream(MStrm) End Sub Listener----- 'Threaded from a listener Sub ClientThread(ByVal Client As TcpClient) Dim MStrm As New MemoryStream Dim Rbuffer(1024) As Byte Dim Tbyte As Byte() Dim NStrm As NetworkStream = Client.GetStream() Dim I As Integer = NStrm.Read(Rbuffer, 0, Rbuffer.Length) Dim Incoming As String = System.Text.Encoding.ASCII.GetString(Rbuffer, 0, I) If Incoming = "Send Picture" then Picture Save(MStrm, Picture.RawFormat) Tbyte = MStrm.ToArray NStrm.Write(Tbyte, 0, Tbyte.Length) End if Client.Close() End Sub

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  • FILE* issue PPU side code

    - by Cristina
    We are working on a homework on CELL programming for college and their feedback response to our questions is kinda slow, thought i can get some faster answers here. I have a PPU side code which tries to open a file passed down through char* argv[], however this doesn't work it cannot make the assignment of the pointer, i get a NULL. Now my first idea was that the file isn't in the correct directory and i copied in every possible and logical place, my second idea is that maybe the PPU wants this pointer in its LS area, but i can't deduce if that's the bug or not. So... My question is what am i doing wrong? I am working with a Fedora 7 SDK Cell, with Eclipse as an IDE. Maybe my argument setup is wrong tho he gets the name of the file correctly. Code on request: images_t *read_bin_data(char *name) { FILE *file; images_t *img; uint32_t *buffer; uint8_t buf; unsigned long fileLen; unsigned long i; //Open file file = (FILE*)malloc(sizeof(FILE)); file = fopen(name, "rb"); printf("[Debug]Opening file %s\n",name); if (!file) { fprintf(stderr, "Unable to open file %s", name); return NULL; } //....... } Main launch: int main(int argc,char* argv[]) { int i,img_width; int modif_this[4] __attribute__ ((aligned(16))) = {1,2,3,4}; images_t *faces, *nonfaces; spe_context_ptr_t ctxs[SPU_THREADS]; pthread_t threads[SPU_THREADS]; thread_arg_t arg[SPU_THREADS]; //intializare img_width img_width = atoi(argv[1]); printf("[Debug]Img size is %i\n",img_width); faces = read_bin_data(argv[3]); //....... } Thanks for the help.

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  • Convert asp.net webforms logic to asp.net MVC

    - by gmcalab
    I had this code in an old asp.net webforms app to take a MemoryStream and pass it as the Response showing a PDF as the response. I am now working with an asp.net MVC application and looking to do this this same thing, but how should I go about showing the MemoryStream as PDF using MVC? Here's my asp.net webforms code: private void ShowPDF(MemoryStream ms) { try { //get byte array of pdf in memory byte[] fileArray = ms.ToArray(); //send file to the user Page.Response.Cache.SetCacheability(HttpCacheability.NoCache); Page.Response.Buffer = true; Response.Clear(); Response.ClearContent(); Response.ClearHeaders(); Response.Charset = string.Empty; Response.ContentType = "application/pdf"; Response.AddHeader("content-length", fileArray.Length.ToString()); Response.AddHeader("Content-Disposition", "attachment;filename=TID.pdf;"); Response.BinaryWrite(fileArray); Response.Flush(); Response.Close(); } catch { // and boom goes the dynamite... } }

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  • What techniques can be used to detect so called "black holes" (a spider trap) when creating a web crawler?

    - by Tom
    When creating a web crawler, you have to design somekind of system that gathers links and add them to a queue. Some, if not most, of these links will be dynamic, which appear to be different, but do not add any value as they are specifically created to fool crawlers. An example: We tell our crawler to crawl the domain evil.com by entering an initial lookup URL. Lets assume we let it crawl the front page initially, evil.com/index The returned HTML will contain several "unique" links: evil.com/somePageOne evil.com/somePageTwo evil.com/somePageThree The crawler will add these to the buffer of uncrawled URLs. When somePageOne is being crawled, the crawler receives more URLs: evil.com/someSubPageOne evil.com/someSubPageTwo These appear to be unique, and so they are. They are unique in the sense that the returned content is different from previous pages and that the URL is new to the crawler, however it appears that this is only because the developer has made a "loop trap" or "black hole". The crawler will add this new sub page, and the sub page will have another sub page, which will also be added. This process can go on infinitely. The content of each page is unique, but totally useless (it is randomly generated text, or text pulled from a random source). Our crawler will keep finding new pages, which we actually are not interested in. These loop traps are very difficult to find, and if your crawler does not have anything to prevent them in place, it will get stuck on a certain domain for infinity. My question is, what techniques can be used to detect so called black holes? One of the most common answers I have heard is the introduction of a limit on the amount of pages to be crawled. However, I cannot see how this can be a reliable technique when you do not know what kind of site is to be crawled. A legit site, like Wikipedia, can have hundreds of thousands of pages. Such limit could return a false positive for these kind of sites. Any feedback is appreciated. Thanks.

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  • How to parse json data from https client in android

    - by Madhan Shanmugam
    I try to fetch data from https client. Same code i used to fetch from http client. but its working fine. when i try to use Https client its not working. i am getting the following error. java.net.UnknownHostException: Host is unresolved: https client address:443 Error Log: 10-27 10:01:08.280: W/System.err(21826): java.net.UnknownHostException: Host is unresolved: https client address.com 443 10-27 10:01:08.290: W/System.err(21826): at java.net.Socket.connect(Socket.java:1037) 10-27 10:01:08.290: W/System.err(21826): at org.apache.http.conn.ssl.SSLSocketFactory.connectSocket(SSLSocketFactory.java:317) 10-27 10:01:08.310: W/System.err(21826): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:129) 10-27 10:01:08.310: W/System.err(21826): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 10-27 10:01:08.310: W/System.err(21826): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 10-27 10:01:08.310: W/System.err(21826): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:348) 10-27 10:01:08.310: W/System.err(21826): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) 10-27 10:01:08.320: W/System.err(21826): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 10-27 10:01:08.320: W/System.err(21826): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465) 10-27 10:01:08.320: W/System.err(21826): at com.myfile.JSONParser.getJSONFromUrl(JSONParser.java:38) 10-27 10:01:08.320: W/System.err(21826): at com.myfile.myfile.processThread(myfile.java:159) 10-27 10:01:08.330: W/System.err(21826): at com.peripay.PERIPay$1$1.run(myfile.java:65) 10-27 10:01:08.330: E/Buffer Error(21826): Error converting result java.lang.NullPointerException 10-27 10:01:08.330: E/JSON Parser(21826): Error parsing data org.json.JSONException: A JSONObject text must begin with '{' at character 0 of

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  • Email function using templates. Includes via ob_start and global vars

    - by Geo
    I have a simple Email() class. It's used to send out emails from my website. <? Email::send($to, $subj, $msg, $options); ?> I also have a bunch of email templates written in plain HTML pierced with a few PHP variables. E.g. /inc/email/templates/account_created.php: <p>Dear <?=$name?>,</p> <p>Thank you for creating an account at <?=$SITE_NAME?>. To login use the link below:</p> <p><a href="https://<?=$SITE_URL?>/account" target="_blank"><?=$SITE_NAME?>/account</a></p> In order to have the PHP vars rendered I had to include the template into my function. But since include does not return the contents but rather just sends it directly to the output, I had to wrap it with the buffer functions: <? abstract class Email { public static function send($to, $subj, $msg, $options = array()) { /* ... */ ob_start(); include '/inc/email/templates/account_created.php'; $msg = ob_get_clean(); /* ... */ } } After that I realized that the PHP vars are not rendered as they are being inside of the function scope, so I had to globalize the variables inside of the template: <? global $SITE_NAME, $SITE_URL, $name; ?> <p>Dear <?=$name?>,</p> ... So the question is whether there is a more elegant solution to this? Mainly I am concerned about my workarounds using ob_start() and global. For some reason that seems to me odd. Or this is pretty much the common practice?

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  • org.apache.http.conn.HttpHostConnectException:Connection to http://172.20.38.143 refused

    - by Passion
    I have developed client server Application .I am accessing mysql with php running on my machine and client running on my cell which is connected to machine.WI-FI is also switched ON. Internet Permission are also added in Manifest file but then also the i encounter error 172.20.38.143 is IP OF MY MACHINE 06-01 13:20:10.391: W/System.err(11157): org.apache.http.conn.HttpHostConnectException: Connection to http://172.20.38.143 refused 06-01 13:20:10.401: W/System.err(11157): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:183) 06-01 13:20:10.401: W/System.err(11157): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 06-01 13:20:10.401: W/System.err(11157): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 06-01 13:20:10.401: W/System.err(11157): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360) 06-01 13:20:10.401: W/System.err(11157): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:674) 06-01 13:20:10.401: W/System.err(11157): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:511) 06-01 13:20:10.401: W/System.err(11157): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:489) 06-01 13:20:10.401: W/System.err(11157): at nineandroid.net.example.library.JSONParser.getJSONFromUrl(JSONParser.java:42) 06-01 13:20:10.401: W/System.err(11157): at nineandroid.net.example.library.UserFunctions.registerUser(UserFunctions.java:59) 06-01 13:20:10.401: W/System.err(11157): at nineandroid.net.example.RegisterActivity$1.onClick(RegisterActivity.java:52) 06-01 13:20:10.411: W/System.err(11157): at android.view.View.performClick(View.java:3567) 06-01 13:20:10.411: W/System.err(11157): at android.view.View$PerformClick.run(View.java:14224) 06-01 13:20:10.411: W/System.err(11157): at android.os.Handler.handleCallback(Handler.java:605) 06-01 13:20:10.411: W/System.err(11157): at android.os.Handler.dispatchMessage(Handler.java:92) 06-01 13:20:10.411: W/System.err(11157): at android.os.Looper.loop(Looper.java:137) 06-01 13:20:10.411: W/System.err(11157): at android.app.ActivityThread.main(ActivityThread.java:4517) 06-01 13:20:10.411: W/System.err(11157): at java.lang.reflect.Method.invokeNative(Native Method) 06-01 13:20:10.411: W/System.err(11157): at java.lang.reflect.Method.invoke(Method.java:511) 06-01 13:20:10.411: W/System.err(11157): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993) 06-01 13:20:10.421: W/System.err(11157): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760) 06-01 13:20:10.421: W/System.err(11157): at dalvik.system.NativeStart.main(Native Method) 06-01 13:20:10.421: W/System.err(11157): Caused by: java.net.ConnectException: failed to connect to /172.20.38.143 (port 80): connect failed: ENETUNREACH (Network is unreachable) 06-01 13:20:10.431: W/System.err(11157): at libcore.io.IoBridge.connect(IoBridge.java:114) 06-01 13:20:10.431: W/System.err(11157): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192) 06-01 13:20:10.431: W/System.err(11157): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459) 06-01 13:20:10.431: W/System.err(11157): at java.net.Socket.connect(Socket.java:848) 06-01 13:20:10.431: W/System.err(11157): at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119) 06-01 13:20:10.431: W/System.err(11157): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144) 06-01 13:20:10.431: W/System.err(11157): ... 20 more 06-01 13:20:10.431: W/System.err(11157): Caused by: libcore.io.ErrnoException: connect failed: ENETUNREACH (Network is unreachable) 06-01 13:20:10.441: W/System.err(11157): at libcore.io.Posix.connect(Native Method) 06-01 13:20:10.441: W/System.err(11157): at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:85) 06-01 13:20:10.441: W/System.err(11157): at libcore.io.IoBridge.connectErrno(IoBridge.java:127) 06-01 13:20:10.441: W/System.err(11157): at libcore.io.IoBridge.connect(IoBridge.java:112) 06-01 13:20:10.441: W/System.err(11157): ... 25 more 06-01 13:20:10.441: E/Buffer Error(11157): Error converting result java.lang.NullPointerException 06-01 13:20:10.451: E/JSON Parser(11157): Error parsing data org.json.JSONException: End of input at character 0 of 06-01 13:20:10.451: D/AndroidRuntime(11157): Shutting down VM 06-01 13:20:10.451: W/dalvikvm(11157): threadid=1: thread exiting with uncaught exception (group=0x40c0aa68) 06-01 13:20:10.451: E/AndroidRuntime(11157): FATAL EXCEPTION: main 06-01 13:20:10.451: E/AndroidRuntime(11157): java.lang.NullPointerException 06-01 13:20:10.451: E/AndroidRuntime(11157): at nineandroid.net.example.RegisterActivity$1.onClick(RegisterActivity.java:56) 06-01 13:20:10.451: E/AndroidRuntime(11157): at android.view.View.performClick(View.java:3567) 06-01 13:20:10.451: E/AndroidRuntime(11157): at android.view.View$PerformClick.run(View.java:14224) 06-01 13:20:10.451: E/AndroidRuntime(11157): at android.os.Handler.handleCallback(Handler.java:605) 06-01 13:20:10.451: E/AndroidRuntime(11157): at android.os.Handler.dispatchMessage(Handler.java:92) 06-01 13:20:10.451: E/AndroidRuntime(11157): at android.os.Looper.loop(Looper.java:137) 06-01 13:20:10.451: E/AndroidRuntime(11157): at android.app.ActivityThread.main(ActivityThread.java:4517) 06-01 13:20:10.451: E/AndroidRuntime(11157): at java.lang.reflect.Method.invokeNative(Native Method) 06-01 13:20:10.451: E/AndroidRuntime(11157): at java.lang.reflect.Method.invoke(Method.java:511) 06-01 13:20:10.451: E/AndroidRuntime(11157): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993) 06-01 13:20:10.451: E/AndroidRuntime(11157): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760) 06-01 13:20:10.451: E/AndroidRuntime(11157): at dalvik.system.NativeStart.main(Native Method) UserFunctions.java to call jsonParser public class UserFunctions { private JSONParser jsonParser; private static String loginURL = "http://172.20.38.143/ah_login_api/"; private static String registerURL = "http://172.20.38.143/ah_login_api/"; private static String login_tag = "login"; private static String register_tag = "register"; // constructor public UserFunctions(){ jsonParser = new JSONParser(); } /** * function make Login Request * @param email * @param password * */ public JSONObject loginUser(String email, String password){ // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("tag", login_tag)); params.add(new BasicNameValuePair("email", email)); params.add(new BasicNameValuePair("password", password)); JSONObject json = jsonParser.getJSONFromUrl(loginURL, params); // return json // Log.e("JSON", json.toString()); return json; } /** * function make Login Request * @param name * @param email * @param password * */ public JSONObject registerUser(String name, String email, String password){ // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("tag", register_tag)); params.add(new BasicNameValuePair("name", name)); params.add(new BasicNameValuePair("email", email)); params.add(new BasicNameValuePair("password", password)); // getting JSON Object JSONObject json = jsonParser.getJSONFromUrl(registerURL, params); // return json return json; } /** * Function get Login status * */ public boolean isUserLoggedIn(Context context){ DatabaseHandler db = new DatabaseHandler(context); int count = db.getRowCount(); if(count > 0){ // user logged in return true; } return false; } /** * Function to logout user * Reset Database * */ public boolean logoutUser(Context context){ DatabaseHandler db = new DatabaseHandler(context); db.resetTables(); return true; } } jsonParser.java public class JSONParser { static InputStream is = null; static JSONObject jObj = null; static String json = ""; // constructor public JSONParser() { } public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) { // Making HTTP request try { // defaultHttpClient DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); httpPost.setEntity(new UrlEncodedFormEntity(params)); HttpResponse httpResponse = httpClient.execute(httpPost); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } try { BufferedReader reader = new BufferedReader(new InputStreamReader( is, "iso-8859-1"), 8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } is.close(); json = sb.toString(); Log.e("JSON", json); } catch (Exception e) { Log.e("Buffer Error", "Error converting result " + e.toString()); } // try parse the string to a JSON object try { jObj = new JSONObject(json); } catch (JSONException e) { Log.e("JSON Parser", "Error parsing data " + e.toString()); } // return JSON String return jObj; } } RegisterActivity.java public class RegisterActivity extends Activity { Button btnRegister; Button btnLinkToLogin; EditText inputFullName; EditText inputEmail; EditText inputPassword; TextView registerErrorMsg; // JSON Response node names private static String KEY_SUCCESS = "success"; private static String KEY_UID = "uid"; private static String KEY_NAME = "name"; private static String KEY_EMAIL = "email"; private static String KEY_CREATED_AT = "created_at"; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.register); // Importing all assets like buttons, text fields inputFullName = (EditText) findViewById(R.id.registerName); inputEmail = (EditText) findViewById(R.id.registerEmail); inputPassword = (EditText) findViewById(R.id.registerPassword); btnRegister = (Button) findViewById(R.id.btnRegister); btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen); registerErrorMsg = (TextView) findViewById(R.id.register_error); // Register Button Click event btnRegister.setOnClickListener(new View.OnClickListener() { public void onClick(View view) { String name = inputFullName.getText().toString(); String email = inputEmail.getText().toString(); String password = inputPassword.getText().toString(); UserFunctions userFunction = new UserFunctions(); JSONObject json = userFunction.registerUser(name, email, password); // check for login response try { if (json.getString(KEY_SUCCESS) != null) { registerErrorMsg.setText(""); String res = json.getString(KEY_SUCCESS); if(Integer.parseInt(res) == 1){ // user successfully registred // Store user details in SQLite Database DatabaseHandler db = new DatabaseHandler(getApplicationContext()); JSONObject json_user = json.getJSONObject("user"); // Clear all previous data in database userFunction.logoutUser(getApplicationContext()); db.addUser(json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL), json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT)); // Launch Dashboard Screen Intent dashboard = new Intent(getApplicationContext(), DashboardActivity.class); // Close all views before launching Dashboard dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); startActivity(dashboard); // Close Registration Screen finish(); }else{ // Error in registration registerErrorMsg.setText("Error occured in registration"); } } } catch (JSONException e) { e.printStackTrace(); } } }); // Link to Login Screen btnLinkToLogin.setOnClickListener(new View.OnClickListener() { public void onClick(View view) { Intent i = new Intent(getApplicationContext(), LoginActivity.class); startActivity(i); // Close Registration View finish(); } }); } }

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  • Speeding up inner-joins and subqueries while restricting row size and table membership

    - by hiffy
    I'm developing an rss feed reader that uses a bayesian filter to filter out boring blog posts. The Stream table is meant to act as a FIFO buffer from which the webapp will consume 'entries'. I use it to store the temporary relationship between entries, users and bayesian filter classifications. After a user marks an entry as read, it will be added to the metadata table (so that a user isn't presented with material they have already read), and deleted from the stream table. Every three minutes, a background process will repopulate the Stream table with new entries (i.e. whenever the daemon adds new entries after the checks the rss feeds for updates). Problem: The query I came up with is hella slow. More importantly, the Stream table only needs to hold one hundred unread entries at a time; it'll reduce duplication, make processing faster and give me some flexibility with how I display the entries. The query (takes about 9 seconds on 3600 items with no indexes): insert into stream(entry_id, user_id) select entries.id, subscriptions_users.user_id from entries inner join subscriptions_users on subscriptions_users.subscription_id = entries.subscription_id where subscriptions_users.user_id = 1 and entries.id not in (select entry_id from metadata where metadata.user_id = 1) and entries.id not in (select entry_id from stream where user_id = 1); The query explained: insert into stream all of the entries from a user's subscription list (subscriptions_users) that the user has not read (i.e. do not exist in metadata) and which do not already exist in the stream. Attempted solution: adding limit 100 to the end speeds up the query considerably, but upon repeated executions will keep on adding a different set of 100 entries that do not already exist in the table (with each successful query taking longer and longer). This is close but not quite what I wanted to do. Does anyone have any advice (nosql?) or know a more efficient way of composing the query?

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  • Wait on multiple condition variables on Linux without unnecessary sleeps?

    - by Joseph Garvin
    I'm writing a latency sensitive app that in effect wants to wait on multiple condition variables at once. I've read before of several ways to get this functionality on Linux (apparently this is builtin on Windows), but none of them seem suitable for my app. The methods I know of are: Have one thread wait on each of the condition variables you want to wait on, which when woken will signal a single condition variable which you wait on instead. Cycling through multiple condition variables with a timed wait. Writing dummy bytes to files or pipes instead, and polling on those. #1 & #2 are unsuitable because they cause unnecessary sleeping. With #1, you have to wait for the dummy thread to wake up, then signal the real thread, then for the real thread to wake up, instead of the real thread just waking up to begin with -- the extra scheduler quantum spent on this actually matters for my app, and I'd prefer not to have to use a full fledged RTOS. #2 is even worse, you potentially spend N * timeout time asleep, or your timeout will be 0 in which case you never sleep (endlessly burning CPU and starving other threads is also bad). For #3, pipes are problematic because if the thread being 'signaled' is busy or even crashes (I'm in fact dealing with separate process rather than threads -- the mutexes and conditions would be stored in shared memory), then the writing thread will be stuck because the pipe's buffer will be full, as will any other clients. Files are problematic because you'd be growing it endlessly the longer the app ran. Is there a better way to do this? Curious for answers appropriate for Solaris as well.

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  • Is my method for avoiding dynamic_cast<> faster than dynamic_cast<> itself ?

    - by ereOn
    Hi, I was answering a question a few minutes ago and it raised to me another one: In one of my projects, I do some network message parsing. The messages are in the form of: [1 byte message type][2 bytes payload length][x bytes payload] The format and content of the payload are determined by the message type. I have a class hierarchy, based on a common class Message. To instanciate my messages, i have a static parsing method which gives back a Message* depending on the message type byte. Something like: Message* parse(const char* frame) { // This is sample code, in real life I obviously check that the buffer // is not NULL, and the size, and so on. switch(frame[0]) { case 0x01: return new FooMessage(); case 0x02: return new BarMessage(); } // Throw an exception here because the mesage type is unknown. } I sometimes need to access the methods of the subclasses. Since my network message handling must be fast, I decived to avoid dynamic_cast<> and I added a method to the base Message class that gives back the message type. Depending on this return value, I use a static_cast<> to the right child type instead. I did this mainly because I was told once that dynamic_cast<> was slow. However, I don't know exactly what it really does and how slow it is, thus, my method might be as just as slow (or slower) but far more complicated. What do you guys think of this design ? Is it common ? Is it really faster than using dynamic_cast<> ? Any detailed explanation of what happen under the hood when one use dynamic_cast<> is welcome !

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  • Emacs: Often switching between Emacs and my IDE's editor, how to automatically 'synch' the files?

    - by WizardOfOdds
    I very often need to do some Emacs magic on some files and I need to go back and forth between my IDE (IntelliJ IDEA) and Emacs. When a change is made under Emacs (and after I've saved the file) and I go back to IntelliJ the change appears immediately (if I recall correctly I configured IntelliJ to "always reload file when a modification is detected on disk" or something like that). I don't even need to reload: as soon as IntelliJ IDEA gains focus, it instantly reloads the file (and I hence have immediately access to the modifications I made from Emacs). So far, so very good. However "the other way round", it doesn't work yet. Can I configure Emacs so that everytime a file is changed on disk it reloads it? Or make Emacs, everytime it "gains focus", verify if any file currently opened has been modified on disk? I know I can start modifying the buffer under Emacs and it shall instantly warn that it has been modified, but I'd rather have it do it immediately (for example if I used my IDE to do some big change, when I come back to Emacs what I see may not be at all anymore what the file contains and it's a bit weird).

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