Search Results

Search found 13619 results on 545 pages for 'memory mapped'.

Page 55/545 | < Previous Page | 51 52 53 54 55 56 57 58 59 60 61 62  | Next Page >

  • Memory allocation for a matrix in C

    - by Snogzvwtr
    Why is the following code resulting in Segmentation fault? (I'm trying to create two matrices of the same size, one with static and the other with dynamic allocation) #include <stdio.h> #include <stdlib.h> //Segmentation fault! int main(){ #define X 5000 #define Y 6000 int i; int a[X][Y]; int** b = (int**) malloc(sizeof(int*) * X); for(i=0; i<X; i++){ b[i] = malloc (sizeof(int) * Y); } } Weirdly enough, if I comment out one of the matrix definitions, the code runs fine. Like this: #include <stdio.h> #include <stdlib.h> //No Segmentation fault! int main(){ #define X 5000 #define Y 6000 int i; //int a[X][Y]; int** b = (int**) malloc(sizeof(int*) * X); for(i=0; i<X; i++){ b[i] = malloc (sizeof(int) * Y); } } or #include <stdio.h> #include <stdlib.h> //No Segmentation fault! int main(){ #define X 5000 #define Y 6000 int i; int a[X][Y]; //int** b = (int**) malloc(sizeof(int*) * X); //for(i=0; i<X; i++){ // b[i] = malloc (sizeof(int) * Y); //} } I'm running gcc on Linux on a 32-bit machine.

    Read the article

  • iphone memory management: alloc and retain properties.

    - by Jonathan
    According to the docs, you do one release per alloc or retain (etc) However what about when using retain propertys? eg: HEADER @property(retain)UIView *someView; IMPLEMENTATION /*in some method*/ UIView *tempView = [[UIView alloc] init]; //<<<<<ALLOC - retain count = +1 [tempView setBackgroundColor:[UIColor redColor]]; self.someView = tempView; ///<<<<<RETAIN - retain count = +2 [tempView release]; ///should I do this? or a different version of the IMPLEMENTATION self.someView = [[UIView alloc] init]; //<<<<<ALLOC & RETAIN - retain count = +2 //now what??? [self.someView release]; ???? EDIT: I didn't make it clear, but I meant what to do in both circumstances, not just the first.

    Read the article

  • iPhone memory management: a release after setting self.someProperty = nil

    - by ddawber
    I am reading the LazyTableImages code that Apple have released and they do something to this effect (in an NSOperation subclass): - (void)dealloc { [myProperty release]; [myProperty2 release]; } - (void)main { // // Parse operation undertaken here // self.myProperty = nil; self.myProperty2 = nil; } My thinking is that they do this in case dealloc is called before setting properties to nil. Is my thinking correct here? Are the releases unnecessary, as self.myProperty = nil effectively releases myProperty? One thing I have noticed in this code is that they don't release all retained objects in dealloc, only some of them, which is really the cause for my confusion. Cheers

    Read the article

  • C - fork() and sharing memory

    - by Ben
    I need my parent and child process to both be able to read and write the same variable (of type int) so it is "global" between the two processes. I'm assuming this would use some sort of cross-process communication and have one variable on one process being updated. I did a quick google and IPC and various techniques come up but I don't know which is the most suitable for my situation. So what technique is best and could you provide a link to a noobs tutorial for it. Thanks.

    Read the article

  • Memory Management iOS dev app doesn't work after a few detail items

    - by user1434846
    I am working on a project with a tableView controller and the detail views contains CMMotionManager.When i open 5 or 6 detailViews all goes well,but after a while the app goes slow and finally crashes.On instruments the only leak is on main.m , also i must say that I'm using ARC and i can't dealloc or realese the instances. Here is the code: First the table view: - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. self.title = @"Movement";//Master View Controller title bar UIImage *image = [UIImage imageNamed:@"jg_navibar.png"]; [self.navigationController.navigationBar setBackgroundImage:image forBarMetrics:UIBarMetricsDefault]; //Init the array with data bodypartsMutableArray = [NSMutableArray arrayWithCapacity:26]; BodypartData *part1 = [[BodypartData alloc] init]; part1.bodypartname = @"Shoulder"; part1.movementname = @"Flexion"; part1.fullimageStartingPosition=[UIImage imageNamed:@"2_shoulder_flexion_end_position.jpg"]; part1.fullimageEndedPosition=[UIImage imageNamed:@"2_shoulder_flexion_end_position.jpg"]; part1.thumbimage=[UIImage imageNamed:@"1_shoulder_flexion_landmarks_thumb.jpg"]; [bodypartsMutableArray addObject:part1]; ......... } then the cell: - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"MyBasicCell"]; BodypartData *part = [self.bodypartsMutableArray objectAtIndex:indexPath.row]; cell.textLabel.text =[NSString stringWithFormat:part.movementname]; cell.detailTextLabel.text =[NSString stringWithFormat:part.bodypartname]; cell.imageView.image =part.thumbimage; return cell; } and the the detailViewdid load: - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. // Init motionManager object and set the Update Interval _motionManager = [[CMMotionManager alloc]init]; _motionManager.deviceMotionUpdateInterval=1/60; //60 Hz [_motionManager startGyroUpdates]; if (_motionManager.gyroAvailable) { _motionManager.gyroUpdateInterval = 1.0/60.0; [_motionManager startDeviceMotionUpdatesToQueue:[NSOperationQueue currentQueue] withHandler: ^(CMDeviceMotion *motion, NSError *error) { CMAttitude *attitude = motion.attitude; //Calculation with rotationMatrix m11 = [NSString stringWithFormat:@"%.02f", attitude.rotationMatrix.m11]; m12 = [NSString stringWithFormat:@"%.02f", attitude.rotationMatrix.m12]; m13 = [NSString stringWithFormat:@"%.02f", attitude.rotationMatrix.m13]; ......... }

    Read the article

  • Simple Obj-C Memory Management Question

    - by yar
    This is from some sample code from a book // On launch, create a basic window - (void)applicationDidFinishLaunching:(UIApplication *)application { UIWindow *window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]; UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:[[HelloController alloc] init]]; [window addSubview:nav.view]; [window makeKeyAndVisible]; } But a release is never called for window nor for nav. Release should be called since alloc was called, right? If #1 is right, then I would need to store a reference to each of these in an instance variable in order to release them in the dealloc? Perhaps I'm wrong all around...

    Read the article

  • how does memory stacks work in javascript

    - by user227353
    When we have code like: function a(){ var x =0; this.add=function(){ alert(x++); } } var test = new a(); test.add(); // alert 0 test.add(); // alert 1 test.add(); // alert 2 How does this work? Doesn't that the value of 'x' in a() should be 'gone' as soon as test = new a() is complete? The stack contains x should also be gone as well, right? Or, does javascript always keep all the stacks ever created in case they will be referenced in future? But that wouldn't be nice, would it...?

    Read the article

  • iphone: memory problems after refactor

    - by agilpwc
    I had a NIB with several view controllers in it. I modified the code and used Interface Builder decomose interface to get all the view controllers in their own Nib. But now with empty core data database, I'm getting "message sent to deallocated instance" errors. Here is the code flow: From the RootViewController this is called: if (self.dogController == nil) { DogViewController *controller = [[DogViewController alloc] initWithNibName:@"DogViewController" bundle:nil]; self.dogController = controller; [controller release]; } self.dogController.managedObjectContext = self.managedObjectContext; [self.navigationController pushViewController:self.dogController animated:YES]; Then in a dogController a button is pressed to insert a new object and the following code is excuted and the error hits on the save, according to the trace NSManagedObjectContext *context = [self.fetchedResultsController managedObjectContext]; NSEntityDescription *entity = [[self.fetchedResultsController fetchRequest] entity]; NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context]; // If appropriate, configure the new managed object. [newManagedObject setValue:[NSDate date] forKey:@"birthDate"]; [newManagedObject setValue:@"-" forKey:@"callName"]; // Save the context. NSError *error = nil; if (![context save:&error]) { Then the error produced in the console is * -[JudgeViewController numberOfSectionsInTableView:]: message sent to deallocated instance 0x598e580 I'm racking my brain for hours and I can't figure out where my minor changes made something messed up. Any ideas?

    Read the article

  • Question about memory usage

    - by sudo rm -rf
    Hi there. I have the following method: +(NSMutableDictionary *)getTime:(float)lat :(float)lon { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; NSMutableDictionary *dictionary = [[NSMutableDictionary alloc] init]; [dictionary setObject:hour forKey:@"hour"]; [dictionary setObject:minute forKey:@"minute"]; [dictionary setObject:ampm forKey:@"ampm"]; return dictionary; } A lot of the method is chopped off, so I think I need the pool for some other stuff in the method. Here's my question. I know that I need to release the following objects: [dictionary release]; [pool release]; However, I can't release the dictionary before I return it, but as soon as I return it the rest of the method isn't performed. What should I do?

    Read the article

  • Objective-C: alloc of object within init of another object (memory management)

    - by Stefan Klumpp
    In my .h file I have: NSMutableArray *myArray; @property (nonatomic, retain) NSMutableArray *myArray; My .m file looks basically like this: @synthesize myArray; - (id) init { self = [super init]; if (self != nil) { self.myArray = .... ? // here I want to create an empty array } return self; } - (void) dealloc { [self.myArray release]; [super dealloc]; } What I'm not sure about is what do to in the init. 1) self.myArray = [[NSMutableArray alloc] init]; 2) NSMutableArray *tmp = [[NSMutableArray alloc] init]; self.myArray = tmp; [tmp release]; Solution 1 doesn't seem right to me, because of my @property (retain) setting I automatically increase the retain counter when setting self.myArray, but additionally I have already a "+1 retain" due to the [NSMutableArray alloc]. Thus the second solution seems more correct to me, even though it is cumbersome. Also am I wondering if self.myArray = ... is actually the same as [self setMyArray:...] and thus does increase the retain count.

    Read the article

  • memory management objective c - returning objects from methods

    - by geeth
    Hi, Please clarify, how to deal with returned objects from methods? Below, I get employee details from GeEmployeetData function with autorelease, 1. Do I have to retain the returned object in Process method? 2. Can I release *emp in Process fucntion? -(void) Process { Employee *emp = [self GeEmployeetData] } +(Employee*) GeEmployeetData{ Employee *emp = [[Employee alloc]init]; //fill entity return [emp autorelease]; }

    Read the article

  • Memory usage of strings (or any other objects) in .Net

    - by ava
    I wrote this little test program: using System; namespace GCMemTest { class Program { static void Main(string[] args) { System.GC.Collect(); System.Diagnostics.Process pmCurrentProcess = System.Diagnostics.Process.GetCurrentProcess(); long startBytes = pmCurrentProcess.PrivateMemorySize64; double kbStart = (double)(startBytes) / 1024.0; System.Console.WriteLine("Currently using " + kbStart + "KB."); { int size = 2000000; string[] strings = new string[size]; for(int i = 0; i < size; i++) { strings[i] = "blabla" + i; } } System.GC.Collect(); pmCurrentProcess = System.Diagnostics.Process.GetCurrentProcess(); long endBytes = pmCurrentProcess.PrivateMemorySize64; double kbEnd = (double)(endBytes) / 1024.0; System.Console.WriteLine("Currently using " + kbEnd + "KB."); System.Console.WriteLine("Leaked " + (kbEnd - kbStart) + "KB."); System.Console.ReadKey(); } } } The output in Release build is: Currently using 18800KB. Currently using 118664KB. Leaked 99864KB. I assume that the GC.collect call will remove the allocated strings since they go out of scope, but it appears it does not. I do not understand nor can I find an explanation for it. Maybe anyone here? Thanks, Alex

    Read the article

  • Httpd Process High memory usage and slow page loads

    - by Abs
    Hello all, I am running wampserver on my windows vista machine. I have been doing this for a long time and it has been working great. I have completed loads of projects with this setup. However, today, without me changing anything (no configuration etc) only PHP code changes, I find that every time I load pages of my site (those with user sessions or access the database) are really slow to load - Over 30 seconds, they use to take 1 or 2 seconds. When I have a look at the task manager, I can see on page loads the httpd process jumps from 10mb to 30mb, 90mb, 120mb, 250mb and then back down again. I have tested previous php code projects and they seem to all be slow as well! What is going on? Thanks all for any help on this confusion issue!

    Read the article

  • Optimizing memory usage and changing file contents with PHP

    - by errata
    In a function like this function download($file_source, $file_target) { $rh = fopen($file_source, 'rb'); $wh = fopen($file_target, 'wb'); if (!$rh || !$wh) { return false; } while (!feof($rh)) { if (fwrite($wh, fread($rh, 1024)) === FALSE) { return false; } } fclose($rh); fclose($wh); return true; } what is the best way to rewrite last few bytes of a file with my custom string? Thanks!

    Read the article

  • Javascript Memory Limit

    - by Dänu
    Hey Guys, I was wondering if there is a "maximum" of data a javascript application can store. I guess this is handled by the browser and that each one has it's limitation? Am I guessing right? Wrong? If there isn't a limit, will a page file be created (wouldn't be very secure I guess).

    Read the article

  • allocating "unmanaged" memory in c#

    - by Blitzz
    Hi, I'm writting a program in c# that uses a C++ library, and for some reason I need to allocate an unmanaged buffer to pass it to the lib. Is there a way to do this in c# ? Basically I would just need to do a malloc in C#... Thanks

    Read the article

  • Objective C memory management question with NSArray

    - by Robert
    I am loading an array with floats like this: NSArray *arr= [NSArray arrayWithObjects: [NSNumber numberWithFloat:1.9], [NSNumber numberWithFloat:1.7], [NSNumber numberWithFloat:1.6], [NSNumber numberWithFloat:1.9],nil]; Now I know this is the correct way of doing it, however I am confused by the retail counts. Each Object is created by the [NSNumber numberWithFloat:] method. This gives the object a retain count of 1 dosnt it? - otherwise the object would be reclaimed The arrayWithObjects: method sends a retain message to each object. This means each object has a retain cont of 2. When the array is de-allocated each object is released leaving them with a retain count of 1. What have I missed?

    Read the article

  • Obj-C memory management for an NSView * instance variable

    - by massimoperi
    My custom view has a subview as an instance variable. Here is a sample interface: @interface MyCustomView : NSView { NSView *aSubview; } @end Then, in the .m file, I initialize aSubView and add it to the custom view. - (id)init { self = [super initWithFrame:CGRectMakeFrame(0.0, 0.0, 320.0, 480.0); if (self) { aSubview = [[NSView alloc] initWithFrame(0.0, 0.0, 100.0, 100.0); [self addSubview:aSubview]; } return self; } Where should I release aSubView? In the -dealloc method? - (void)dealloc { [aSubView release]; [super dealloc]; } Or directly after adding it to the custom view in the -init method? - (id)init { [...] [self addSubview:aSubview]; [aSubview release]; [...] } Which one is the best implementation?

    Read the article

  • Memory alignment in C

    - by user1758245
    Here is a snippet: #pragma pack(4) struct s1 { char a; long b; }; #pragma pack() #pragma pack(2) struct s2 { char c; struct s1 st1; }; #pragma pack() #pragma pack(2) struct s3 { char a; long b; }; #pragma pack() #pragma pack(4) struct s4 { char c; struct s3 st3; }; #pragma pack() I though sizeof(s4) should be 10 or 12. But it turns out to be 8. I am using Visual C++ 6.0. Could someone tell me why?

    Read the article

< Previous Page | 51 52 53 54 55 56 57 58 59 60 61 62  | Next Page >