Search Results

Search found 3140 results on 126 pages for 'stencil buffer'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 2/126 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • Java HTTP Requests Buffer size

    - by behrk2
    Hello, I have an HTTP Request Dispatcher class that works most of the time, but I had noticed that it "stalls" when receiving larger requests. After looking into the problem, I thought that perhaps I wasn't allocating enough bytes to the buffer. Before, I was doing: byte[] buffer = new byte[10000]; After changing it to 20000, it seems to have stopped stalling: String contentType = connection.getHeaderField("Content-type"); ByteArrayOutputStream baos = new ByteArrayOutputStream(); InputStream responseData = connection.openInputStream(); byte[] buffer = new byte[20000]; int bytesRead = responseData.read(buffer); while (bytesRead > 0) { baos.write(buffer, 0, bytesRead); bytesRead = responseData.read(buffer); } baos.close(); connection.close(); Am I doing this right? Is there anyway that I can dynamically set the number of bytes for the buffer based on the size of the request? Thanks...

    Read the article

  • Intelligent "Subtraction" of one text logfile from another

    - by Vi
    Example: Application generates large text log file A with many different messages. It generates similarly large log file B when does not function correctly. I want to see what messages in file B are essentially new, i.e. to filter-out everything from A. Trivial prototype is: Sort | uniq both files Join files sort | uniq -c grep -v "^2" This produces symmetric difference and inconvenient. How to do it better? (including non-symmetric difference and preserving of messages order in B) Program should first analyse A and learn which messages are common, then analyse B showing with messages needs attention. Ideally it should automatically disregard things like timestamps, line numbers or other volatile things. Example. A: 0:00:00.234 Received buffer 0x324234 0:00:00.237 Processeed buffer 0x324234 0:00:00.238 Send buffer 0x324255 0:00:03.334 Received buffer 0x324255 0:00:03.337 Processeed buffer 0x324255 0:00:03.339 Send buffer 0x324255 0:00:05.171 Received buffer 0x32421A 0:00:05.173 Processeed buffer 0x32421A 0:00:05.178 Send buffer 0x32421A B: 0:00:00.134 Received buffer 0x324111 0:00:00.137 Processeed buffer 0x324111 0:00:00.138 Send buffer 0x324111 0:00:03.334 Received buffer 0x324222 0:00:03.337 Processeed buffer 0x324222 0:00:03.338 Error processing buffer 0x324222 0:00:03.339 Send buffer 0x3242222 0:00:05.271 Received buffer 0x3242FA 0:00:05.273 Processeed buffer 0x3242FA 0:00:05.278 Send buffer 0x3242FA 0:00:07.280 Send buffer 0x3242FA failed Result: 0:00:03.338 Error processing buffer 0x324222 0:00:07.280 Send buffer 0x3242FA failed One of ways of solving it can be something like that: Split each line to logical units: 0:00:00.134 Received buffer 0x324111,0:00:00.134,Received,buffer,0x324111,324111,Received buffer, \d:\d\d:\d\d\.\d\d\d, \d+:\d+:\d+.\d+, 0x[0-9A-F]{6}, ... It should find individual words, simple patterns in numbers, common layouts (e.g. "some date than text than number than text than end_of_line"), also handle combinations of above. As it is not easy task, user assistance (adding regexes with explicit "disregard that","make the main factor","don't split to parts","consider as date/number","take care of order/quantity of such messages" rules) should be supported (but not required) for it. Find recurring units and "categorize" lines, filter out too volatile things like timestamps, addresses or line numbers. Analyse the second file, find things that has new logical units (one-time or recurring), or anything that will "amaze" the system which has got used to the first file. Example of doing some bit of this manually: $ cat A | head -n 1 0:00:00.234 Received buffer 0x324234 $ cat A | egrep -v "Received buffer" | head -n 1 0:00:00.237 Processeed buffer 0x324234 $ cat A | egrep -v "Received buffer|Processeed buffer" | head -n 1 0:00:00.238 Send buffer 0x324255 $ cat A | egrep -v "Received buffer|Processeed buffer|Send buffer" | head -n 1 $ cat B | egrep -v "Received buffer|Processeed buffer|Send buffer" 0:00:03.338 Error processing buffer 0x324222 0:00:07.280 Send buffer 0x3242FA failed This is a boring thing (there are a lot of message types); also I can accidentally include some too broad pattern. Also it can't handle complicated things like interrelation between messages. I know that it is AI-related. May be there are already developed tools?

    Read the article

  • Unable to get Stencil Buffer to work in iOS 4+ (5.0 works fine). [OpenGL ES 2.0]

    - by MurderDev
    So I am trying to use a stencil buffer in iOS for masking/clipping purposes. Do you guys have any idea why this code may not work? This is everything I have associated with Stencils. On iOS 4 I get a black screen. On iOS 5 I get exactly what I expect. The transparent areas of the image I drew in the stencil are the only areas being drawn later. Code is below. This is where I setup the frameBuffer, depth and stencil. In iOS the depth and stencil are combined. -(void)setupDepthBuffer { glGenRenderbuffers(1, &depthRenderBuffer); glBindRenderbuffer(GL_RENDERBUFFER, depthRenderBuffer); glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8_OES, self.frame.size.width * [[UIScreen mainScreen] scale], self.frame.size.height * [[UIScreen mainScreen] scale]); } -(void)setupFrameBuffer { glGenFramebuffers(1, &frameBuffer); glBindFramebuffer(GL_FRAMEBUFFER, frameBuffer); glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, colorRenderBuffer); glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthRenderBuffer); glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, depthRenderBuffer); // Check the FBO. if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) { NSLog(@"Failure with framebuffer generation: %d", glCheckFramebufferStatus(GL_FRAMEBUFFER)); } } This is how I am setting up and drawing the stencil. (Shader code below.) glEnable(GL_STENCIL_TEST); glDisable(GL_DEPTH_TEST); glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE); glDepthMask(GL_FALSE); glStencilFunc(GL_ALWAYS, 1, -1); glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE); glColorMask(0, 0, 0, 0); glClear(GL_STENCIL_BUFFER_BIT); machineForeground.shader = [StencilEffect sharedInstance]; [machineForeground draw]; machineForeground.shader = [BasicEffect sharedInstance]; glDisable(GL_STENCIL_TEST); glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE); glDepthMask(GL_TRUE); Here is where I am using the stencil. glEnable(GL_STENCIL_TEST); glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP); glStencilFunc(GL_EQUAL, 1, -1); ...Draw Stuff here glDisable(GL_STENCIL_TEST); Finally here is my fragment shader. varying lowp vec2 TexCoordOut; uniform sampler2D Texture; void main(void) { lowp vec4 color = texture2D(Texture, TexCoordOut); if(color.a < 0.1) gl_FragColor = color; else discard; }

    Read the article

  • How to determine the used size of device associated's buffer

    - by dubbaluga
    Hi, when mounting a device without the "sync" option, e. g. by invoking the following: mount -o async /dev/sdc1 /mnt a buffer is associated with a device to optimize (speed) read/write operations. Is there a way to determine the size of this buffer? Another question that comes into my mind is, if it's possible to find out how much of it is used currently. This can be interesting to determine the time it would take to "sync" or "umount" slow devices, such as flash-based media. Thanks in advance for your answers, Rainer

    Read the article

  • Switching to some emacs shell buffers moves the cursor to the beginning of the buffer

    - by yuvilio
    I run Emacs 24 with prelude and a few shells that i invoke at the start ( e.g.: (shell "*shell*_spare") ). When i switch to some of them (C-x b), my cursor lands at the beginning of the buffer, rather than when it last left off (typically the end of the buffer after the last command I ran). The strange thing is that this does not happen for all the shell buffers that I set up in the same way but with different names. When I switch to them, the cursor is where it last left off. Any ideas how I can make the cursor always be where it last was or at the bottom?

    Read the article

  • Illustration of buffer overflows for students (linux, C)

    - by osgx
    Hello My friend is teacher of first-year CS students. We want to show them buffer overflow exploitation. But modern distribs are protected from simples buffer overflows: HOME=`perl -e "print 'A'x269"` one_widely_used_utility_is_here --help on debian (blame it) Caught signal 11, on modern commercial redhat *** buffer overflow detected ***: /usr/bin/one_widely_used_utility_is_here terminated ======= Backtrace: ========= /lib/libc.so.6(__chk_fail+0x41)[0xc321c1] /lib/libc.so.6(__strcpy_chk+0x43)[0xc315e3] /usr/bin/one_widely_used_utility_is_here[0x805xxxc] /usr/bin/one_widely_used_utility_is_here[0x804xxxc] /lib/libc.so.6(__libc_start_main+0xdc)[0xb61e9c] /usr/bin/one_widely_used_utility_is_here[0x804xxx1] ======= Memory map: ======== 00336000-00341000 r-xp 00000000 08:02 2751047 /lib/libgcc_s-4.1.2-20080825.so.1 00341000-00342000 rwxp 0000a000 08:02 2751047 /lib/libgcc_s-4.1.2-20080825.so.1 008f3000-008f4000 r-xp 008f3000 00:00 0 [vdso] The same detector fails for more synthetic examples from the internet. How can we demonstrate buffer overflow with modern non-GPL distribs (there is no debian in classes) How can we DISABLE canary word checking in stack ? DISABLE checking variants of strcpy/strcat ? write an example (in plain C) with working buffer overrun ?

    Read the article

  • How to prevent buffer overflow in C/C++?

    - by alexpov
    Hello, i am using the following code to redirect stdout to a pipe, then read all the data from the pipe to a buffer. I have 2 problems: first problem: when i send a string (after redirection) bigger then the pipe's BUFF_SIZE, the program stops responding (deadlock or something). second problem: when i try to read from a pipe before something was sent to stdout. I get the same response, the program stops responding - _read command stuck's ... The issue is that i don't know the amount of data that will be sent to the pipe after the redirection. The first problem, i don't know how to handle and i'll be glad for help. The second problem i solved by a simple workaround, right after the redirection i print space character to stdout. but i guess that this solution is not the correct one ... #include <fcntl.h> #include <io.h> #include <iostream> #define READ 0 #define WRITE 1 #define BUFF_SIZE 5 using namespace std; int main() { int stdout_pipe[2]; int saved_stdout; saved_stdout = _dup(_fileno(stdout)); // save stdout if(_pipe(stdout_pipe,BUFF_SIZE, O_TEXT) != 0 ) // make a pipe { exit(1); } fflush( stdout ); if(_dup2(stdout_pipe[1], _fileno(stdout)) != 0 ) //redirect stdout to the pipe { exit(1); } ios::sync_with_stdio(); setvbuf( stdout, NULL, _IONBF, 0 ); //anything sent to stdout goes now to the pipe //printf(" ");//workaround for the second problem printf("123456");//first problem char buffer[BUFF_SIZE] = {0}; int nOutRead = 0; nOutRead = _read(stdout_pipe[READ], buffer, BUFF_SIZE); //second problem buffer[nOutRead] = '\0'; // reconnect stdout if (_dup2(saved_stdout, _fileno(stdout)) != 0 ) { exit(1); } ios::sync_with_stdio(); printf("buffer: %s\n", buffer); } Thanks, Alex

    Read the article

  • BitBlting multiple images to buffer

    - by Anonymous
    So I've made a class which draws a transparant image to a buffer. the buffer is a HDC which has been used blackness on. What I am trying to do is draw three images to this buffer. Which means I am using this function three times. After that's done, I output it to the screen (using SRCCOPYing the buffer). But what I get to see is just the third image and blackness. void draw_buffer(HDC buffer, int draw_x, int draw_y) { BitBlt(this-main, draw_x, draw_y, this-img_width, this-img_height, this-image, this-mask_x, this-mask_y, SRCAND); BitBlt(this-main, draw_x, draw_y, this-img_width, this-img_height, this-image, this-img_x, this-img_y, SRCPAINT); BitBlt(buffer, 0, 0, 800, 600, this-main, 0, 0, SRCCOPY); } At initiation, this-main becomes this: this->main = CreateCompatibleDC(GetDC(0)); this->bitmap = CreateCompatibleBitmap(GetDC(0),800,600); SelectObject(this->main, this->bitmap); What is wrong with my code?

    Read the article

  • who free's setvbuf buffer?

    - by Evan Teran
    So I've been digging into how the stdio portion of libc is implemented and I've come across another question. Looking at man setvbuf I see the following: When the first I/O operation occurs on a file, malloc(3) is called, and a buffer is obtained. This makes sense, your program should have a malloc in it for I/O unless you actually use it. My gut reaction to this is that libc will clean up its own mess here. Which I can only assume it does because valgrind reports no memory leaks (they could of course do something dirty and not allocate it via malloc directly... but we'll assume that it literally uses malloc for now). But, you can specify your own buffer too... int main() { char *p = malloc(100); setvbuf(stdio, p, _IOFBF, 100); puts("hello world"); } Oh no, memory leak! valgrind confirms it. So it seems that whenever stdio allocates a buffer on its own, it will get deleted automatically (at the latest on program exit, but perhaps on stream close). But if you specify the buffer explicitly, then you must clean it up yourself. There is a catch though. The man page also says this: You must make sure that the space that buf points to still exists by the time stream is closed, which also happens at program termination. For example, the following is invalid: Now this is getting interesting for the standard streams. How would one properly clean up a manually allocated buffer for them, since they are closed in program termination? I could imagine a "clean this up when I close flag" inside the file struct, but it get hairy because if I read this right doing something like this: setvbuf(stdio, 0, _IOFBF, 100); printf("hello "); setvbuf(stdio, 0, _IOLBF, 100); printf("world\n"); would cause 2 allocations by the standard library because of this sentence: If the argument buf is NULL, only the mode is affected; a new buffer will be allocated on the next read or write operation.

    Read the article

  • [ebp + 6] instead of +8 in a JIT compiler

    - by David Titarenco
    I'm implementing a simplistic JIT compiler in a VM I'm writing for fun (mostly to learn more about language design) and I'm getting some weird behavior, maybe someone can tell me why. First I define a JIT "prototype" both for C and C++: #ifdef __cplusplus typedef void* (*_JIT_METHOD) (...); #else typedef (*_JIT_METHOD) (); #endif I have a compile() function that will compile stuff into ASM and stick it somewhere in memory: void* compile (void* something) { // grab some memory unsigned char* buffer = (unsigned char*) malloc (1024); // xor eax, eax // inc eax // inc eax // inc eax // ret -> eax should be 3 /* WORKS! buffer[0] = 0x67; buffer[1] = 0x31; buffer[2] = 0xC0; buffer[3] = 0x67; buffer[4] = 0x40; buffer[5] = 0x67; buffer[6] = 0x40; buffer[7] = 0x67; buffer[8] = 0x40; buffer[9] = 0xC3; */ // xor eax, eax // mov eax, 9 // ret 4 -> eax should be 9 /* WORKS! buffer[0] = 0x67; buffer[1] = 0x31; buffer[2] = 0xC0; buffer[3] = 0x67; buffer[4] = 0xB8; buffer[5] = 0x09; buffer[6] = 0x00; buffer[7] = 0x00; buffer[8] = 0x00; buffer[9] = 0xC3; */ // push ebp // mov ebp, esp // mov eax, [ebp + 6] ; wtf? shouldn't this be [ebp + 8]!? // mov esp, ebp // pop ebp // ret -> eax should be the first value sent to the function /* WORKS! */ buffer[0] = 0x66; buffer[1] = 0x55; buffer[2] = 0x66; buffer[3] = 0x89; buffer[4] = 0xE5; buffer[5] = 0x66; buffer[6] = 0x66; buffer[7] = 0x8B; buffer[8] = 0x45; buffer[9] = 0x06; buffer[10] = 0x66; buffer[11] = 0x89; buffer[12] = 0xEC; buffer[13] = 0x66; buffer[14] = 0x5D; buffer[15] = 0xC3; // mov eax, 5 // add eax, ecx // ret -> eax should be 50 /* WORKS! buffer[0] = 0x67; buffer[1] = 0xB8; buffer[2] = 0x05; buffer[3] = 0x00; buffer[4] = 0x00; buffer[5] = 0x00; buffer[6] = 0x66; buffer[7] = 0x01; buffer[8] = 0xC8; buffer[9] = 0xC3; */ return buffer; } And finally I have the main chunk of the program: void main (int argc, char **args) { DWORD oldProtect = (DWORD) NULL; int i = 667, j = 1, k = 5, l = 0; // generate some arbitrary function _JIT_METHOD someFunc = (_JIT_METHOD) compile(NULL); // windows only #if defined _WIN64 || defined _WIN32 // set memory permissions and flush CPU code cache VirtualProtect(someFunc,1024,PAGE_EXECUTE_READWRITE, &oldProtect); FlushInstructionCache(GetCurrentProcess(), someFunc, 1024); #endif // this asm just for some debugging/testing purposes __asm mov ecx, i // run compiled function (from wherever *someFunc is pointing to) l = (int)someFunc(i, k); // did it work? printf("result: %d", l); free (someFunc); _getch(); } As you can see, the compile() function has a couple of tests I ran to make sure I get expected results, and pretty much everything works but I have a question... On most tutorials or documentation resources, to get the first value of a function passed (in the case of ints) you do [ebp+8], the second [ebp+12] and so forth. For some reason, I have to do [ebp+6] then [ebp+10] and so forth. Could anyone tell me why?

    Read the article

  • Usage of current-buffer in emacs?

    - by Zubair
    I'm using emacs and I have written a script which uses "current-buffer". However the emacs system doesn't recognise "current-buffer". When I try "M - x current-buffer" i get the response: no match : Any idea what I'm doing wrong?

    Read the article

  • How can I mark a pixel in the stencil buffer?

    - by János Turánszki
    I never used the stencil buffer for anything until now, but I want to change this. I have an idea of how it should work: the gpu discards or keeps rasterized pixels before the pixel shader based on the stencil buffer value on the given position and some stencil operation. What I don't know is how would I mark a pixel in the stencil buffer with a specific value. For example I draw my scene and want to mark everything which is drawn with a specific material (this material could be looked up from a texture so ideally I should mark the pixel in the pixel shader), so that later when I do some post processing on my scene I would only do it on the marked pixels. I didn't find anything on the internet besides how to set up a stencil buffer and explaining the different stencil operations. I was expecting to find some System-Value semantics like SV_Depth to write to in the pixel shader (because the stencil buffer shares the same resource with the depth buffer in D3D11), but there is no such thing on MSDN. So how should I do this? If I am misunderstanding something please help me clear that up.

    Read the article

  • function's return address is different from its supposed value, buffer overflow,

    - by ultrajohn
    Good day everyone! I’m trying to understand how buffer overflow works. I’m doing this for my project in a computer security course I’m taking. Right now, I’m in the process of determining the address of the function’s return address which I’m supposed to change to perform a buffer overflow attack. I’ve written a simple program based from an example I’ve read in the internet. What this program does is it creates an integer pointer that will be made to point to the address of the function return address in the stack. To do this, (granted I understand how a function/program variables get organized in the stack), I add 8 to the buffer variable’ address and set it as the value of ret. I’m not doing anything here that would change the address contained in the location of func’s return address. here's the program: Output of the program when gets excecuted: As you can see, I’m printing the address of the variables buffer and ret. I’ve added an additional statement printing the value of the ret variable (supposed location of func return address, so this should print the address of the next instruction which will get executed after func returns from execution). Here is the dump which shows the supposed address of the instruction to be executed after func returns. (Underlined in green) As you can see, that value is way different from the value printed contained in the variable ret. My question is, why are they different? (of course in the assumption that what I’ve done are all right). Else, what have I done wrong? Is my understanding of the program’s runtime stack wrong? Please, help me understand this. My project is due nextweek and I’ve barely touched it yet. I’m sorry if I’m being demanding, I badly need your help.

    Read the article

  • C# Application crashes with Buffer Overrun in deployed (.exe) version, but not in Visual Studio

    - by Ben
    Hi, I have a c# Windows Forms application that runs perfectly from within Visual Studio, but crashes when its deployed and run from the .exe. It crashes with a Buffer Overrun error...and its pretty clear that this error is not being thrown from within my code. Instead, windows must be detecting some sort of buffer overrun and shutting down the application from the outside. I don't think there's one specific line of code that is causing it..it simply happens intermittently. Does anybody have any thoughts on what the possible causes of a Buffer Overrun error might be, and why it would only occur in the deployed application and not when run from with Visual Studio? Thanks in advance, Ben

    Read the article

  • Buffer management for socket application best practice

    - by Poni
    Having a Windows IOCP app............ I understand that for async i/o operation (on network) the buffer must remain valid for the duration of the send/read operation. So for each connection I have one buffer for the reading. For sending I use buffers to which I copy the data to be sent. When the sending operation completes I release the buffer so it can be reused. So far it's nice and not of a big issue. What remains unclear is how do you guys do this? Another thing is that even when having things this way, I mean multi-buffers, the receiver side might be flooded (talking from experience) with data. Even setting SO_RCVBUF to 25MB didn't help in my testings. So what should I do? Have a to-be-sent queue?

    Read the article

  • How much buffer does NetworkStream and TcpClient have?

    - by Earlz
    Hello, We are writing a TCPServer and Client program. How much space is there in the TcpClient buffer? Like, at what point will it begin to throw away data? We are trying to determine if the TcpClient can be blocking or if it should go into it's own background thread(so that the buffer can not get full)..

    Read the article

  • Buffer size: N*sizeof(type) or sizeof(var)? C++

    - by flyout
    I am just starting with cpp and I've been following different examples to learn from them, and I see that buffer size is set in different ways, for example: char buffer[255]; StringCchPrintf(buffer, sizeof(buffer), TEXT("%s"), X); VS char buffer[255]; StringCchPrintf(buffer, 255*sizeof(char), TEXT("%s"), X); Which one is the correct way to use it? I've seen this in other functions like InternetReadFile, ZeroMemory and MultiByteToWideChar.

    Read the article

  • C# File IO with Streams - Best Memory Buffer Size

    - by AJ
    Hi, I am writing a small IO library to assist with a larger (hobby) project. A part of this library performs various functions on a file, which is read / written via the FileStream object. On each StreamReader.Read(...) pass, I fire off an event which will be used in the main app to display progress information. The processing that goes on in the loop is vaired, but is not too time consuming (it could just be a simple file copy, for example, or may involve encryption...). My main question is: What is the best memory buffer size to use? Thinking about physical disk layouts, I could pick 2k, which would cover a CD sector size and is a nice multiple of a 512 byte hard disk sector. Higher up the abstraction tree, you could go for a larger buffer which could read an entire FAT cluster at a time. I realise with today's PC's, I could go for a more memory hungry option (a couple of MiB, for example), but then I increase the time between UI updates and the user perceives a less responsive app. As an aside, I'm eventually hoping to provide a similar interface to files hosted on FTP / HTTP servers (over a local network / fastish DSL). What would be the best memory buffer size for those (again, a "best-case" tradeoff between perceived responsiveness vs. performance). Thanks in advance for any ideas, Adam

    Read the article

  • Need help with buffer overrun.

    - by Morinar
    I've got a buffer overrun I absolutely can't see to figure out (in C). First of all, it only happens maybe 10% of the time or so. The data that it is pulling from the DB each time doesn't seem to be all that much different between executions... at least not different enough for me to find any discernible pattern as to when it happens. The exact message from Visual Studio is this: A buffer overrun has occurred in hub.exe which has corrupted the program's internal state. Press Break to debug the program or Continue to terminate the program. For more details please see Help topic 'How to debug Buffer Overrun Issues'. If I debug, I find that it is broken in __report_gsfailure() which I'm pretty sure is from the /GS flag on the compiler and also signifies that this is an overrun on the stack rather than the heap. I can also see the function it threw this on as it was leaving, but I can't see anything in there that would cause this behavior, the function has also existed for a long time (10+ years, albeit with some minor modifications) and as far as I know, this has never happened. I'd post the code of the function, but it's decently long and references a lot of proprietary functions/variables/etc. I'm basically just looking for either some idea of what I should be looking for that I haven't or perhaps some tools that may help. Unfortunately, nearly every tool I've found only helps with debugging overruns on the heap, and unless I'm mistaken, this is on the stack. Thanks in advance.

    Read the article

  • Flush kernel's TCP buffer with `MSG_MORE`-flagged packets

    - by timn
    send()'s man page reveals the MSG_MORE flag which is asserted to act like TCP_CORK. I have a wrapper function around send(): int SocketConnection_Write(SocketConnection *this, void *buf, int len) { errno = 0; int sent = send(this->fd, buf, len, MSG_NOSIGNAL); if (errno == EPIPE || errno == ENOTCONN) { throw(exc, &SocketConnection_NotConnectedException); } else if (errno == ECONNRESET) { throw(exc, &SocketConnection_ConnectionResetException); } else if (sent != len) { throw(exc, &SocketConnection_LengthMismatchException); } return sent; } Assuming I want to use the kernel buffer, I could go with TCP_CORK, enable whenever it is necessary and then disable it to flush the buffer. But on the other hand, thereby the need for an additional system call arises. Thus, the usage of MSG_MORE seems more appropriate to me. I'd simply change the above send() line to: int sent = send(this->fd, buf, len, MSG_NOSIGNAL | MSG_MORE); According to lwm.net, packets will be flushed automatically if they are large enough: If an application sets that option on a socket, the kernel will not send out short packets. Instead, it will wait until enough data has shown up to fill a maximum-size packet, then send it. When TCP_CORK is turned off, any remaining data will go out on the wire. But this section only refers to TCP_CORK. Now, what is the proper way to flush MSG_MORE packets? I can only think of two possibilities: Call send() with an empty buffer and without MSG_MORE being set Re-apply the TCP_CORK option as described on this page Unfortunately the whole topic is very poorly documented and I couldn't find much on the Internet. I am also wondering how to check that everything works as expected? Obviously running the server through strace' is not an option. So the only simplest way would be to usenetcat' and then look at its `strace' output? Or will the kernel handle traffic differently transmitted over a loopback interface?

    Read the article

  • Android depth buffer issue: Advice for anyone experiencing problem

    - by Andrew Smith
    I've wasted around 30 hours this week writing and re-writing code, believing that I had misunderstood how the OpenGL depth buffer works. Everything I tried, failed. I have now resolved my problem by finding what may be an error in the Android implementation of OpenGL. See this API entry: http://www.opengl.org/sdk/docs/man/xhtml/glClearDepth.xml void glClearDepth(GLclampd depth); Specifies the depth value used when the depth buffer is cleared. The initial value is 1. Android's implementation has two versions of this command: glClearDepthx which takes an integer value, clamped 0-1 glClearDepthf which takes a floating point value, clamped 0-1 If you use glClearDepthf(1) then you get the results you would expect. If you use glClearDepthx(1), as I was doing then you get different results. (Note that 1 is the default value, but calling the command with the argument 1 produces different results than not calling it at all.) Quite what is happening I do not know, but the depth buffer was being cleared to a value different from what I had specified.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >