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  • OpenGL Application displays only 1 frame

    - by Avi
    EDIT: I have verified that the problem is not the VBO class or the vertex array class, but rather something else. I have a problem where my vertex buffer class works the first time its called, but displays nothing any other time its called. I don't know why this is, and it's also the same in my vertex array class. I'm calling the functions in this order to set up the buffers: enable client states bind buffers set buffer / array data unbind buffers disable client states Then in the draw function, that's called every frame: enable client states bind buffers set pointers unbind buffers bind index buffer draw elements unbind index buffer disable client states Is there something wrong with the order in which I'm calling the functions, or is it a more specific code error? EDIT: here's some of the code Code for setting pointers: //element is the vertex attribute being drawn (e.g. normals, colors, etc.) static void makeElementPointer(VertexBufferElements::VBOElement element, Shader *shade, void *elementLocation) { //elementLocation is BUFFER_OFFSET(n) if a buffer is bound switch (element) { .... glVertexPointer(3, GL_FLOAT, 0, elementLocation); //changes based on element .... //but I'm only dealing with } //vertices for now } And that's basically all the code that isn't just a straight OpenGL function call.

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  • Data breakpoints to find points where data gets broken

    - by raccoon_tim
    When working with a large code base, finding reasons for bizarre bugs can often be like finding a needle in a hay stack. Finding out why an object gets corrupted without no apparent reason can be quite daunting, especially when it seems to happen randomly and totally out of context. Scenario Take the following scenario as an example. You have defined the a class that contains an array of characters that is 256 characters long. You now implement a method for filling this buffer with a string passed as an argument. At this point you mistakenly expect the buffer to be 256 characters long. At some point you notice that you require another character buffer and you add that after the previous one in the class definition. You now figure that you don’t need the 256 characters that the first member can hold and you shorten that to 128 to conserve space. At this point you should start thinking that you also have to modify the method defined above to safeguard against buffer overflow. It so happens, however, that in this not so perfect world this does not cross your mind. Buffer overflow is one of the most frequent sources for errors in a piece of software and often one of the most difficult ones to detect, especially when data is read from an outside source. Many mass copy functions provided by the C run-time provide versions that have boundary checking (defined with the _s suffix) but they can not guard against hard coded buffer lengths that at some point get changed. Finding the bug Getting back to the scenario, you’re now wondering why does the second string get modified with data that makes no sense at all. Luckily, Visual Studio provides you with a tool to help you with finding just these kinds of errors. It’s called data breakpoints. To add a data breakpoint, you first run your application in debug mode or attach to it in the usual way, and then go to Debug, select New Breakpoint and New Data Breakpoint. In the popup that opens, you can type in the memory address and the amount of bytes you wish to monitor. You can also use an expression here, but it’s often difficult to come up with an expression for data in an object allocated on the heap when not in the context of a certain stack frame. There are a couple of things to note about data breakpoints, however. First of all, Visual Studio supports a maximum of four data breakpoints at any given time. Another important thing to notice is that some C run-time functions modify memory in kernel space which does not trigger the data breakpoint. For instance, calling ReadFile on a buffer that is monitored by a data breakpoint will not trigger the breakpoint. The application will now break at the address you specified it to. Often you might immediately spot the issue but the very least this feature can do is point you in the right direction in search for the real reason why the memory gets inadvertently modified. Conclusions Data breakpoints are a great feature, especially when doing a lot of low level operations where multiple locations modify the same data. With the exception of some special cases, like kernel memory modification, you can use it whenever you need to check when memory at a certain location gets changed on purpose or inadvertently.

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  • How do I put different textures on different walls? LWJGL

    - by lehermj
    So far I have it so you are running around in a box, but all of the walls are the same texture! I've loaded up other textures for the walls (I want the walls a different texture than the floor) but it seems as if its being ignored... Here's my code: int floorTexture = glGenTextures(); { InputStream in = null; try { in = new FileInputStream("floor.png"); PNGDecoder decoder = new PNGDecoder(in); ByteBuffer buffer = BufferUtils.createByteBuffer(4 * decoder.getWidth() * decoder.getHeight()); decoder.decode(buffer, decoder.getWidth() * 4, Format.RGBA); buffer.flip(); glBindTexture(GL_TEXTURE_2D, floorTexture); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, decoder.getWidth(), decoder.getHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer); glBindTexture(GL_TEXTURE_2D, floorTexture); } catch (FileNotFoundException ex) { System.err.println("Failed to find the texture files."); ex.printStackTrace(); Display.destroy(); System.exit(1); } catch (IOException ex) { System.err.println("Failed to load the texture files."); ex.printStackTrace(); Display.destroy(); System.exit(1); } finally { if (in != null) { try { in.close(); } catch (IOException e) { e.printStackTrace(); } } } } int wallTexture = glGenTextures(); { InputStream in = null; try { in = new FileInputStream("walls.png"); PNGDecoder decoder = new PNGDecoder(in); ByteBuffer buffer = BufferUtils.createByteBuffer(4 * decoder.getWidth() * decoder.getHeight()); decoder.decode(buffer, decoder.getWidth() * 4, Format.RGBA); buffer.flip(); glBindTexture(GL_TEXTURE_2D, wallTexture); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, decoder.getWidth(), decoder.getHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer); glBindTexture(GL_TEXTURE_2D, wallTexture); } catch (FileNotFoundException ex) { System.err.println("Failed to find the texture files."); ex.printStackTrace(); Display.destroy(); System.exit(1); } catch (IOException ex) { System.err.println("Failed to load the texture files."); ex.printStackTrace(); Display.destroy(); System.exit(1); } finally { if (in != null) { try { in.close(); } catch (IOException e) { e.printStackTrace(); } } } } int ceilingDisplayList = glGenLists(1); glNewList(ceilingDisplayList, GL_COMPILE); glBegin(GL_QUADS); glTexCoord2f(0, 0); glVertex3f(-gridSize, ceilingHeight, -gridSize); glTexCoord2f(gridSize * 10 * tileSize, 0); glVertex3f(gridSize, ceilingHeight, -gridSize); glTexCoord2f(gridSize * 10 * tileSize, gridSize * 10 * tileSize); glVertex3f(gridSize, ceilingHeight, gridSize); glTexCoord2f(0, gridSize * 10 * tileSize); glVertex3f(-gridSize, ceilingHeight, gridSize); glEnd(); glEndList(); int wallDisplayList = glGenLists(1); glNewList(wallDisplayList, GL_COMPILE); glBegin(GL_QUADS); // North wall glTexCoord2f(0, 0); glVertex3f(-gridSize, floorHeight, -gridSize); glTexCoord2f(0, gridSize * 10 * tileSize); glVertex3f(gridSize, floorHeight, -gridSize); glTexCoord2f(gridSize * 10 * tileSize, gridSize * 10 * tileSize); glVertex3f(gridSize, ceilingHeight, -gridSize); glTexCoord2f(gridSize * 10 * tileSize, 0); glVertex3f(-gridSize, ceilingHeight, -gridSize); // West wall glTexCoord2f(0, 0); glVertex3f(-gridSize, floorHeight, -gridSize); glTexCoord2f(gridSize * 10 * tileSize, 0); glVertex3f(-gridSize, ceilingHeight, -gridSize); glTexCoord2f(gridSize * 10 * tileSize, gridSize * 10 * tileSize); glVertex3f(-gridSize, ceilingHeight, +gridSize); glTexCoord2f(0, gridSize * 10 * tileSize); glVertex3f(-gridSize, floorHeight, +gridSize); // East wall glTexCoord2f(0, 0); glVertex3f(+gridSize, floorHeight, -gridSize); glTexCoord2f(gridSize * 10 * tileSize, 0); glVertex3f(+gridSize, floorHeight, +gridSize); glTexCoord2f(gridSize * 10 * tileSize, gridSize * 10 * tileSize); glVertex3f(+gridSize, ceilingHeight, +gridSize); glTexCoord2f(0, gridSize * 10 * tileSize); glVertex3f(+gridSize, ceilingHeight, -gridSize); // South wall glTexCoord2f(0, 0); glVertex3f(-gridSize, floorHeight, +gridSize); glTexCoord2f(gridSize * 10 * tileSize, 0); glVertex3f(-gridSize, ceilingHeight, +gridSize); glTexCoord2f(gridSize * 10 * tileSize, gridSize * 10 * tileSize); glVertex3f(+gridSize, ceilingHeight, +gridSize); glTexCoord2f(0, gridSize * 10 * tileSize); glVertex3f(+gridSize, floorHeight, +gridSize); glEnd(); glEndList(); int floorDisplayList = glGenLists(1); glNewList(floorDisplayList, GL_COMPILE); glBegin(GL_QUADS); glTexCoord2f(0, 0); glVertex3f(-gridSize, floorHeight, -gridSize); glTexCoord2f(0, gridSize * 10 * tileSize); glVertex3f(-gridSize, floorHeight, gridSize); glTexCoord2f(gridSize * 10 * tileSize, gridSize * 10 * tileSize); glVertex3f(gridSize, floorHeight, gridSize); glTexCoord2f(gridSize * 10 * tileSize, 0); glVertex3f(gridSize, floorHeight, -gridSize); glEnd(); glEndList();

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  • Possible / How to render to multiple back buffers, using one as a shader resource when rendering to the other, and vice versa?

    - by Raptormeat
    I'm making a game in Direct3D10. For several of my rendering passes, I need to change the behavior of the pass depending on what is already rendered on the back buffer. (For example, I'd like to do some custom blending- when the destination color is dark, do one thing; when it is light, do another). It looks like I'll need to create multiple render targets and render back and forth between them. What's the best way to do this? Create my own render textures, use them, and then copy the final result into the back buffer. Create multiple back buffers, render between them, and then present the last one that was rendered to. Create one render texture, and one back buffer, render between them, and just ensure that the back buffer is the final target rendered to I'm not sure which of these is possible, and if there are any performance issues that aren't obvious. Clearly my preference would be to have 2 rather than 3 default render targets, if possible.

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  • Multiple vulnerabilities in libexif

    - by Umang_D
    CVE DescriptionCVSSv2 Base ScoreComponentProduct and Resolution CVE-2012-2812 Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability 6.4 libexif Solaris 11 11/11 SRU 12.4 CVE-2012-2813 Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability 6.4 CVE-2012-2814 Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability 7.5 CVE-2012-2836 Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability 6.4 CVE-2012-2837 Numeric Errors vulnerability 5.0 CVE-2012-2840 Numeric Errors vulnerability 7.5 CVE-2012-2841 Numeric Errors vulnerability 7.5 CVE-2012-2845 Numeric Errors vulnerability 6.4 This notification describes vulnerabilities fixed in third-party components that are included in Oracle's product distributions.Information about vulnerabilities affecting Oracle products can be found on Oracle Critical Patch Updates and Security Alerts page.

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  • Can printf change its parameters??

    - by martani_net
    EDIT: complete code with main is here http://codepad.org/79aLzj2H and once again this is were the weird behavious is happening for (i = 0; i<tab_size; i++) { //CORRECT OUTPUT printf("%s\n", tableau[i].capitale); printf("%s", tableau[i].pays); printf("%s\n", tableau[i].commentaire); //WRONG OUTPUT //printf("%s --- %s --- %s |\n", tableau[i].capitale, tableau[i].pays, tableau[i].commentaire); } I have an array of the following strcuture struct T_info { char capitale[255]; char pays[255]; char commentaire[255]; }; struct T_info *tableau; This is how the array is populated int advance(FILE *f) { char c; c = getc(f); if(c == '\n') return 0; while(c != EOF && (c == ' ' || c == '\t')) { c = getc(f); } return fseek(f, -1, SEEK_CUR); } int get_word(FILE *f, char * buffer) { char c; int count = 0; int space = 0; while((c = getc(f)) != EOF) { if (c == '\n') { buffer[count] = '\0'; return -2; } if ((c == ' ' || c == '\t') && space < 1) { buffer[count] = c; count ++; space++; } else { if (c != ' ' && c != '\t') { buffer[count] = c; count ++; space = 0; } else /* more than one space*/ { advance(f); break; } } } buffer[count] = '\0'; if(c == EOF) return -1; return count; } void fill_table(FILE *f,struct T_info *tab) { int line = 0, column = 0; fseek(f, 0, SEEK_SET); char buffer[MAX_LINE]; char c; int res; int i = 0; while((res = get_word(f, buffer)) != -999) { switch(column) { case 0: strcpy(tab[line].capitale, buffer); column++; break; case 1: strcpy(tab[line].pays, buffer); column++; break; default: strcpy(tab[line].commentaire, buffer); column++; break; } /*if I printf each one alone here, everything works ok*/ //last word in line if (res == -2) { if (column == 2) { strcpy(tab[line].commentaire, " "); } //wrong output here printf("%s -- %s -- %s\n", tab[line].capitale, tab[line].pays, tab[line].commentaire); column = 0; line++; continue; } column = column % 3; if (column == 0) { line++; } /*EOF reached*/ if(res == -1) return; } return ; } Edit : trying this printf("%s -- ", tab[line].capitale); printf("%s --", tab[line].pays); printf("%s --\n", tab[line].commentaire); gives me as result -- --abi -- Emirats arabes unis I expect to get Abu Dhabi -- Emirats arabes unis -- Am I missing something?

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  • IOException during blocking network NIO in JDK 1.7

    - by Bass
    I'm just learning NIO, and here's the short example I've written to test how a blocking NIO can be interrupted: class TestBlockingNio { private static final boolean INTERRUPT_VIA_THREAD_INTERRUPT = true; /** * Prevent the socket from being GC'ed */ static Socket socket; private static SocketChannel connect(final int port) { while (true) { try { final SocketChannel channel = SocketChannel.open(new InetSocketAddress(port)); channel.configureBlocking(true); return channel; } catch (final IOException ioe) { try { Thread.sleep(1000); } catch (final InterruptedException ie) { } continue; } } } private static byte[] newBuffer(final int length) { final byte buffer[] = new byte[length]; for (int i = 0; i < length; i++) { buffer[i] = (byte) 'A'; } return buffer; } public static void main(final String args[]) throws IOException, InterruptedException { final int portNumber = 10000; new Thread("Reader") { public void run() { try { final ServerSocket serverSocket = new ServerSocket(portNumber); socket = serverSocket.accept(); /* * Fully ignore any input from the socket */ } catch (final IOException ioe) { ioe.printStackTrace(); } } }.start(); final SocketChannel channel = connect(portNumber); final Thread main = Thread.currentThread(); final Thread interruptor = new Thread("Inerruptor") { public void run() { System.out.println("Press Enter to interrupt I/O "); while (true) { try { System.in.read(); } catch (final IOException ioe) { ioe.printStackTrace(); } System.out.println("Interrupting..."); if (INTERRUPT_VIA_THREAD_INTERRUPT) { main.interrupt(); } else { try { channel.close(); } catch (final IOException ioe) { System.out.println(ioe.getMessage()); } } } } }; interruptor.setDaemon(true); interruptor.start(); final ByteBuffer buffer = ByteBuffer.allocate(32768); int i = 0; try { while (true) { buffer.clear(); buffer.put(newBuffer(buffer.capacity())); buffer.flip(); channel.write(buffer); System.out.print('X'); if (++i % 80 == 0) { System.out.println(); Thread.sleep(100); } } } catch (final ClosedByInterruptException cbie) { System.out.println("Closed via Thread.interrupt()"); } catch (final AsynchronousCloseException ace) { System.out.println("Closed via Channel.close()"); } } } In the above example, I'm writing to a SocketChannel, but noone is reading from the other side, so eventually the write operation hangs. This example works great when run by JDK-1.6, with the following output: Press Enter to interrupt I/O XXXX Interrupting... Closed via Thread.interrupt() — meaning that only 128k of data was written to the TCP socket's buffer. When run by JDK-1.7 (1.7.0_25-b15 and 1.7.0-u40-b37), however, the very same code bails out with an IOException: Press Enter to interrupt I/O XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXX Exception in thread "main" java.io.IOException: Broken pipe at sun.nio.ch.FileDispatcherImpl.write0(Native Method) at sun.nio.ch.SocketDispatcher.write(SocketDispatcher.java:47) at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:93) at sun.nio.ch.IOUtil.write(IOUtil.java:65) at sun.nio.ch.SocketChannelImpl.write(SocketChannelImpl.java:487) at com.example.TestBlockingNio.main(TestBlockingNio.java:109) Can anyone explain this different behaviour?

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  • How Do You Get the bufspec While Using Vimdiff Through Git

    - by Elizabeth Buckwalter
    I've read Vimdiff and Viewing differences with Vimdiff plus doing various google searches using things like "vimdiff multiple", "vimdiff git", "vimdiff commands" etc. When using do or diffg I get the error "More than two buffers in diff mode, don't know which one to use". When using diffg v:fname_in I get "No matching buffer for v:fname_in". From the vimdiff documentation: :[range]diffg[et] [bufspec] Modify the current buffer to undo difference with another buffer. If [bufspec] is given, that buffer is used. If [bufspec] refers to the current buffer then nothing happens. Otherwise this only works if there is one other buffer in diff mode. and more: When 'diffexpr' is not empty, Vim evaluates to obtain a diff file in the format mentioned. These variables are set to the file names used: v:fname_in original file v:fname_new new version of the same file v:fname_out resulting diff file So, I need to get the name of bufspec, but the default variables (fname_in, fname_new, and fname_out) aren't set. I ran the command git mergetool on a linux box through a terminal. [Edit] A partial solution that bred more questions. I used the "filename" at the bottom of the buffer. It's only a half answer, because occasionally I get a file does not exist error. I believe it's consistently the remote version of the file that "does not exist". I suspect this has something to do with git and indexing. How do you get the bufspec value consistently while using vimdiff through git-mergetool?

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  • video streaming over http in blackberry

    - by ysnky
    hi all, while i was searching video player over http, i found the article which is located at this url; http://www.blackberry.com/knowledgecenterpublic/livelink.exe/fetch/2000/348583/800332/1089414/Stream ing_media_-_Start_to_finish.html?nodeid=2456737&ve rnum=0 i can run by adding ";deviceside=true" at the end of url. it works fine in the jde4.5 simulator. it gets 3gp videos from my local server. i tested with 580kb files and works fine. but when i get the same file from my server (not local, real server) i have problems with big files (e.g 580 kb). it plays 180kb files (but sometimes it does not play this file either) but not plays 580kb file. and also i deployed my application to my 9000 device it sometimes plays small file (180kb) but never plays big file (580kb). why it plays if it is on my local file, not play in real world? i ve stucked for days. hope you help me. and also the code at the url given below is not work, the only code i ve found is the above. blackberry.com/knowledgecenterpublic/livelink.exe/fetch/2000/348583/800332/1089414/How_To _-_Play_video_within_a_BlackBerry_smartphone_appli cation.html?nodeid=1383173&vernum=0 btw, there is no method such as resize(long param) of CircularByteBuffer class. so i comment relavent line (buffer.resize(buffer.getSize() + (buffer.getSize() * percent / 100)); as shown below. public void increaseBufferCapacity(int percent) { if(percent < 0){ log(0, "FAILED! SP.setBufferCapacity() - " + percent); throw new IllegalArgumentException("Increase factor must be positive.."); } synchronized(readLock){ synchronized(connectionLock){ synchronized(userSeekLock){ synchronized(mediaIStream){ log(0, "SP.setBufferCapacity() - " + percent); //buffer.resize(buffer.getSize() + (buffer.getSize() * percent / 100)); this.bufferCapacity = buffer.getSize(); } } } } } thanks in advance.

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  • Instantiating class with custom allocator in shared memory

    - by recipriversexclusion
    I'm pulling my hair due to the following problem: I am following the example given in boost.interprocess documentation to instantiate a fixed-size ring buffer buffer class that I wrote in shared memory. The skeleton constructor for my class is: template<typename ItemType, class Allocator > SharedMemoryBuffer<ItemType, Allocator>::SharedMemoryBuffer( unsigned long capacity ){ m_capacity = capacity; // Create the buffer nodes. m_start_ptr = this->allocator->allocate(); // allocate first buffer node BufferNode* ptr = m_start_ptr; for( int i = 0 ; i < this->capacity()-1; i++ ) { BufferNode* p = this->allocator->allocate(); // allocate a buffer node } } My first question: Does this sort of allocation guarantee that the buffer nodes are allocated in contiguous memory locations, i.e. when I try to access the n'th node from address m_start_ptr + n*sizeof(BufferNode) in my Read() method would it work? If not, what's a better way to keep the nodes, creating a linked list? My test harness is the following: // Define an STL compatible allocator of ints that allocates from the managed_shared_memory. // This allocator will allow placing containers in the segment typedef allocator<int, managed_shared_memory::segment_manager> ShmemAllocator; //Alias a vector that uses the previous STL-like allocator so that allocates //its values from the segment typedef SharedMemoryBuffer<int, ShmemAllocator> MyBuf; int main(int argc, char *argv[]) { shared_memory_object::remove("MySharedMemory"); //Create a new segment with given name and size managed_shared_memory segment(create_only, "MySharedMemory", 65536); //Initialize shared memory STL-compatible allocator const ShmemAllocator alloc_inst (segment.get_segment_manager()); //Construct a buffer named "MyBuffer" in shared memory with argument alloc_inst MyBuf *pBuf = segment.construct<MyBuf>("MyBuffer")(100, alloc_inst); } This gives me all kinds of compilation errors related to templates for the last statement. What am I doing wrong?

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  • How do I import and call unmanaged C dll with ansi string "char *" pointer string from VB.net?

    - by Warren P
    I have written my own function, which in C would be declared like this, using standard Win32 calling conventions: int Thing( char * command, char * buffer, int * BufSize); I have the following amount of VB figured out, which should import the dll and call this function, wrapping it up to make it easy to call Thing("CommandHere",GetDataBackHere): Imports Microsoft.VisualBasic Imports System.Runtime.InteropServices Imports System Imports System.Text Namespace dllInvocationSpace Public Class dllInvoker ' tried attributes but could not make it build: ' <DllImport("Thing1.dll", False, CallingConvention.Cdecl, CharSet.Ansi, "Baton", True, True, False, True)> Declare Ansi Function Thing Lib "Thing1.dll" (ByVal Command As String, ByRef Buffer As String, ByRef BufferLength As Integer) Shared Function dllCall(ByVal Command As String, ByRef Results As String) As Integer Dim Buffer As StringBuilder = New StringBuilder(65536) Dim retCode As Integer Dim bufsz As Integer bufsz = 65536 retCode = Thing(Command, Buffer, bufsz) Results = Buffer Return retCode End Function End Class End Namespace The current code doesn't build, because although I think I should be able to create a "buffer" that the C Dll can write data back into using a string builder, I haven't got it quite right. (Value of type System.Text.STringBuilder cannot be converted to 'String'). I have looked all over the newsgroups and forums and can not find an example where the C dll needs to pass between 1 and 64kbytes of data back (char *buffer, int bufferlen) to visual basic.net.

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  • linux new/delete, malloc/free large memory blocks

    - by brian_mk
    Hi folks, We have a linux system (kubuntu 7.10) that runs a number of CORBA Server processes. The server software uses glibc libraries for memory allocation. The linux PC has 4G physical memory. Swap is disabled for speed reasons. Upon receiving a request to process data, one of the server processes allocates a large data buffer (using the standard C++ operator 'new'). The buffer size varies depening upon a number of parameters but is typically around 1.2G Bytes. It can be up to about 1.9G Bytes. When the request has completed, the buffer is released using 'delete'. This works fine for several consecutive requests that allocate buffers of the same size or if the request allocates a smaller size than the previous. The memory appears to be free'd ok - otherwise buffer allocation attempts would eventually fail after just a couple of requests. In any case, we can see the buffer memory being allocated and freed for each request using tools such as KSysGuard etc. The problem arises when a request requires a buffer larger than the previous. In this case, operator 'new' throws an exception. It's as if the memory that has been free'd from the first allocation cannot be re-allocated even though there is sufficient free physical memory available. If I kill and restart the server process after the first operation, then the second request for a larger buffer size succeeds. i.e. killing the process appears to fully release the freed memory back to the system. Can anyone offer an explanation as to what might be going on here? Could it be some kind of fragmentation or mapping table size issue? I am thinking of replacing new/delete with malloc/free and use mallopt to tune the way the memory is being released to the system. BTW - I'm not sure if it's relevant to our problem, but the server uses Pthreads that get created and destroyed on each processing request. Cheers, Brian.

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  • Detect TCP connection close when playing Flash video

    - by JoJo
    On the Flash client side, how do I detect when the server purposely closes the TCP connection to its video stream? I'll need to take action when this occurs - maybe attempt to restart the video or display an error message. Currently, the connection closing and the connection being slow look the same to me. The NetStream object ushers a NetStream.Play.Stop event in both cases. When the connection is slow, it usually recovers by itself within seconds. I wish to only take action when the connection is closed, not when it is slow. Here's how my general setup looks like. It's the basic NetConnection-NetStream-Video setup. this.vidConnection = new NetConnection(); this.vidConnection.addEventListener(AsyncErrorEvent.ASYNC_ERROR, this.connectionAsyncError); this.vidConnection.addEventListener(IOErrorEvent.IO_ERROR, this.connectionIoError); this.vidConnection.addEventListener(NetStatusEvent.NET_STATUS, this.connectionNetStatus); this.vidConnection.connect(null); this.vidStream = new NetStream(this.vidConnection); this.vidStream.addEventListener(AsyncErrorEvent.ASYNC_ERROR, this.streamAsyncError); this.vidStream.addEventListener(IOErrorEvent.IO_ERROR, this.streamIoError); this.vidStream.addEventListener(NetStatusEvent.NET_STATUS, this.streamNetStatus); this.vid.attachNetStream(this.vidStream); None of the error events fire when the server closes the TCP or when the connection freezes up. Only the NetStream.Play.Stop event fires. Here's a trace of what happens from initially playing the video to the TCP connection closing. connection net status = NetConnection.Connect.Success playStream(http://192.168.0.44/flv/4d29104a9aefa) NetStream.Play.Start NetStream.Buffer.Flush NetStream.Buffer.Full NetStream.Buffer.Empty checkDimensions 0 0 onMetaData NetStream.Buffer.Full NetStream.Buffer.Flush checkDimensions 960 544 NetStream.Buffer.Empty NetStream.Buffer.Flush NetStream.Play.Stop

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  • How do I set the LRECL in C#.NET?

    - by donde
    I have been trying to ftp a dtl file from .net to, what I beleive, is an AS400. The error being reported back to me is: "One or more lines have been truncated" and the admin is saying the file is coming over with 256 lines that have variable length columns. I found this explanation online: we have to establish defaults because no specifics about the file exist. The default RECFM is V and LRECL is 256. This means that SAS will scan the input record looking for the CR & LF to tell us that we are at the EOR. If the marker isn't found within the limit of the LRECL, SAS discards the data from the LRECL value to the end of the record and adds a message to the Log that "One or more lines have been truncated". So I need to set the LRECL. How do I do this in C# .NET? FtpWebRequest ftp = (FtpWebRequest)FtpWebRequest.Create(ftpfullpath); ftp.Credentials = new NetworkCredential(user, pwd); ftp.KeepAlive = false; ftp.UseBinary = false; ftp.Method = WebRequestMethods.Ftp.UploadFile; FileStream fs = File.OpenRead(inputfilepath + ftpfileName); byte[] buffer = new byte[fs.Length]; fs.Read(buffer, 0, buffer.Length); fs.Close(); Stream ftpstream = ftp.GetRequestStream(); int i = 0; int intBlock = 1786; int intBuffLeft = buffer.Length; while (i < buffer.Length) { if (intBuffLeft >= 1786) { ftpstream.Write(buffer, i, intBlock); } else { ftpstream.Write(buffer, i, intBuffLeft); } i += intBlock; intBuffLeft -= 1786; } ftpstream.Close();

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  • Read whole ASCII file into C++ std::string

    - by Arrieta
    Hello, I need to read a whole file into memory and place it in a C++ std::string. If I were to read it into a char, the answer would be very simple: std::ifstream t; int lenght; t.open("file.txt", "r"); // open input file t.seekg(0, std::ios::end); // go to the end length = t.tellg(); // report location (this is the lenght) t.seekg(0, std::ios::beg); // go back to the beginning buffer = new char[length]; // allocate memory for a buffer of appropriate dimension t.read(buffer, length); // read the whole file into the buffer t.close(); // close file handle // ... do stuff with buffer here ... Now, I want to do the exact same thing, but using a std::string instead of a char. I want to avoid loops, i. e., I don't want to: std::ifstream t; t.open("file.txt", "r"); std::string buffer; std::string line; while(t){ std::getline(t, line); // ... append line to buffer and go on } t.close() any ideas?

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  • Why do I need to close fds when reading and writing to the pipe?

    - by valentimsousa
    However, what if one of my processes needs to continuously write to the pipe while the other pipe needs to read? This example seems to work only for one write and one read. I need multi read and write void executarComandoURJTAG(int newSock) { int input[2], output[2], estado, d; pid_t pid; char buffer[256]; char linha[1024]; pipe(input); pipe(output); pid = fork(); if (pid == 0) {// child close(0); close(1); close(2); dup2(input[0], 0); dup2(output[1], 1); dup2(output[1], 2); close(input[1]); close(output[0]); execlp("jtag", "jtag", NULL); } else { // parent close(input[0]); close(output[1]); do { read(newSock, linha, 1024); /* Escreve o buffer no pipe */ write(input[1], linha, strlen(linha)); close(input[1]); while ((d = read(output[0], buffer, 255))) { //buffer[d] = '\0'; write(newSock, buffer, strlen(buffer)); puts(buffer); } write(newSock, "END", 4); } while (strcmp(linha, "quit") != 0); } }

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  • Saving information in the IO System

    - by djTeller
    Hi Kernel Gurus, I need to write a kernel module that simulate a "multicaster" Using the /proc file system. Basically it need to support the following scenarios: 1) allow one write access to the /proc file and many read accesses to the /proc file. 2) The module should have a buffer of the contents last successful write. Each write should be matched by a read from all reader. Consider scenario 2, a writer wrote something and there are two readers (A and B), A read the content of the buffer, and then A tried to read again, in this case it should go into a wait_queue and wait for the next message, it should not get the same buffer again. I need to keep a map of all the pid's that already read the current buffer, and in case they try to read again and the buffer was not changed, they should be blocked until there is a new buffer. I'm trying to figure it there is a way i can save that info without a map. I heard there are some redundant fields inside the I/O system the I can use to flag a process if it already read the current buffer. Can someone give me a tip where should i look for that field ? how can i save info on the current process without keeping a "map" of pid's and buffers ? Thanks!

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  • ORA-06502: PL/SQL: numeric or value error: character string buffer too small with Oracle aggregate f

    - by Tunde
    Good day gurus, I have a script that populates tables on a regular basis that crashed and gave the above error. The strange thing is that it has been running for close to 3 months on the production system with no problems and suddenly crashed last week. There has not been any changes on the tables as far as I know. Has anyone encountered something like this before? I believe it has something to do with the aggregate functions I'm implementing in it; but it worked initially. please; kindly find attached the part of the script I've developed into a procedure that I reckon gives the error. CREATE OR REPLACE PROCEDURE V1 IS --DECLARE v_a VARCHAR2(4000); v_b VARCHAR2(4000); v_c VARCHAR2(4000); v_d VARCHAR2(4000); v_e VARCHAR2(4000); v_f VARCHAR2(4000); v_g VARCHAR2(4000); v_h VARCHAR2(4000); v_i VARCHAR2(4000); v_j VARCHAR2(4000); v_k VARCHAR2(4000); v_l VARCHAR2(4000); v_m VARCHAR2(4000); v_n NUMBER(10); v_o VARCHAR2(4000); -- -- Procedure that populates DEMO table BEGIN -- Delete all from the DEMO table DELETE FROM DEMO; -- Populate fields in DEMO from DEMOV1 INSERT INTO DEMO(ID, D_ID, CTR_ID, C_ID, DT_NAM, TP, BYR, ENY, ONG, SUMM, DTW, REV, LD, MD, STAT, CRD) SELECT ID, D_ID, CTR_ID, C_ID, DT_NAM, TP, TO_NUMBER(TO_CHAR(BYR,'YYYY')), TO_NUMBER(TO_CHAR(NVL(ENY,SYSDATE),'YYYY')), CASE WHEN ENY IS NULL THEN 'Y' ELSE 'N' END, SUMMARY, DTW, REV, LD, MD, '1', SYSDATE FROM DEMOV1; -- LOOP THROUGH DEMO TABLE FOR j IN (SELECT ID, CTR_ID, C_ID FROM DEMO) LOOP Select semic_concat(TXTDESC) INTO v_a From GEOT WHERE ID = j.ID; SELECT COUNT(*) INTO v_n FROM MERP M, PROJ P WHERE M.MID = P.COD AND ID = j.ID AND PROAC IS NULL; IF (v_n > 0) THEN Select semic_concat(PRO) INTO v_b FROM MERP M, PROJ P WHERE M.MID = P.COD AND ID = j.ID; ELSE Select semic_concat(PRO || '(' || PROAC || ')' ) INTO v_b FROM MERP M, PROJ P WHERE M.MID = P.COD AND ID = j.ID; END IF; Select semic_concat(VOCNAME('P02',COD)) INTO v_c From PAR WHERE ID = j.ID; Select semic_concat(VOCNAME('L05',COD)) INTO v_d From INST WHERE ID = j.ID; Select semic_concat(NVL(AUTHOR,'Anon') ||' ('||to_char(PUB,'YYYY')||') '||TITLE||', '||EDT) INTO v_e From REFE WHERE ID = j.ID; Select semic_concat(NAM) INTO v_f FROM EDM E, EDO EO WHERE E.EDMID = EO.EDOID AND ID = j.ID; Select semic_concat(VOCNAME('L08', COD)) INTO v_g FROM AVA WHERE ID = j.ID; SELECT or_concat(NAM) INTO v_o FROM CON WHERE ID = j.ID AND NAM = 'Unknown'; IF (v_o = 'Unknown') THEN Select or_concat(JOBTITLE || ' (' || EMAIL || ')') INTO v_h FROM CON WHERE ID = j.ID; ELSE Select or_concat(NAM || ' (' || EMAIL || ')') INTO v_h FROM CON WHERE ID = j.ID; END IF; Select commaencap_concat(COD) INTO v_i FROM PAR WHERE ID = j.ID; IF (v_i = ',') THEN v_i := null; ELSE Select commaencap_concat(COD) INTO v_i FROM PAR WHERE ID = j.ID; END IF; Select commaencap_concat(COD) INTO v_j FROM INST WHERE ID = j.ID; IF (v_j = ',') THEN v_j := null; ELSE Select commaencap_concat(COD) INTO v_j FROM INST WHERE ID = j.ID; END IF; Select commaencap_concat(COD) INTO v_k FROM SAR WHERE ID = j.ID; IF (v_k = ',') THEN v_k := null; ELSE Select commaencap_concat(COD) INTO v_k FROM SAR WHERE ID = j.ID; END IF; Select commaencap_concat(CONID) INTO v_l FROM CON WHERE ID = j.ID; IF (v_l = ',') THEN v_l := null; ELSE Select commaencap_concat(CONID) INTO v_l FROM CON WHERE ID = j.ID; END IF; Select commaencap_concat(PROID) INTO v_m FROM PRO WHERE ID = j.ID; IF (v_m = ',') THEN v_m := null; ELSE Select commaencap_concat(PROID) INTO v_m FROM PRO WHERE ID = j.ID; END IF; -- UPDATE DEMO TABLE UPDATE DEMO SET GEOC = v_a, PRO = v_b, PAR = v_c, INS = v_d, REFER = v_e, ORGR = v_f, AVAY = v_g, CON = v_h, DTH = v_i, INST = v_j, SA = v_k, CC = v_l, EDPR = v_m, CTR = (SELECT NAM FROM EDM WHERE EDMID = j.CTR_ID), COLL = (SELECT NAM FROM EDM WHERE EDMID = j.C_ID) WHERE ID = j.ID; END LOOP; END V1; / The aggregate functions, commaencap_concat (encapsulates with a comma), or_concat (concats with an or) and semic_concat(concats with a semi-colon). the remaining tables used are all linked to the main table DEMO. I have checked the column sizes and there seems to be no problem. I tried executing the SELECT statements alone and they give the same error without populating the tables. Any clues? Many thanks for your anticipated support.

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  • Groovy Grails, How do you stream or buffer a large file in a Controller's response?

    - by Julian Noye
    Hi Guys I have a controller that makes a connection to a url to retrieve a csv file. I am able to send the file in the response using the following code, this works fine. def fileURL = "www.mysite.com/input.csv" def thisUrl = new URL(fileURL); def connection = thisUrl.openConnection(); def output = connection.content.text; response.setHeader "Content-disposition", "attachment; filename=${'output.csv'}" response.contentType = 'text/csv' response.outputStream << output response.outputStream.flush() However I don't think this method is inappropriate for a large file, as the whole file is loaded into the controllers memory. I want to be able to read the file chunk by chunk and write the file to the response chunk by chunk. Any ideas?

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  • WSASend() with more than one buffer - could complete incomplete?

    - by Poni
    Say I post the following WSASend call (Windows I/O completion ports without callback functions): void send_data() { WSABUF wsaBuff[2]; wsaBuff[0].len = 20; wsaBuff[1].len = 25; WSASend(sock, &wsaBuff[0], 2, ......); } When I get the "write_done" notification from the completion port, is it possible that wsaBuff[1] will be sent completely (25 bytes) yet wsaBuff[0] will be only partially sent (say 7 bytes)?

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  • How to get the data buffer of screen in screen stack in Android?

    - by Glory Jiang
    Currently I want to develop one Activity to allow the user to see the screens/activites of all running tasks , then the user can select one of them to switch it to foreground. As I known, HTC Sence seems already to have this implementation for Home screen, to display the thumbnail of all Home panels in one screen. Does anybody know how to access screen stack in Android? Thanks.

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

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

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  • How to replace a region in emacs with yank buffer contents?

    - by Mad Wombat
    When I use VIM or most modeless editors (Eclipse, NetBeans etc.) I frequently do the following. If I have similar text blocks and I need to change them all, I will change one, copy it (or use non-deleting yank), select next block I need and paste the changed version over it. If I do the same thing in emacs (select region and paste with C-y), it doesn't replace the region, it just pastes at the cursor position. What is the way to do this in emacs?

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  • VST plugin : using FFT on audio input buffer with arbitrary size, how ?

    - by Led
    I'm getting interested in programming a VST plugin, and I have a basic knowledge of audio dsp's and FFT's. I'd like to use VST.Net, and I'm wondering how to implement an FFT-based effect. The process-code looks like public override void Process(VstAudioBuffer[] inChannels, VstAudioBuffer[] outChannels) If I'm correct, normally the FFT would be applied on the input, some processing would be done on the FFT'd data, and then an inverse-FFT would create the processed soundbuffer. But since the FFT works on a specified buffersize that will most probably be different then the (arbitrary) amount of input/output-samples, how would you handle this ?

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