Search Results

Search found 12445 results on 498 pages for 'memory fragmentation'.

Page 382/498 | < Previous Page | 378 379 380 381 382 383 384 385 386 387 388 389  | Next Page >

  • Forcing a templated object to construct from a pointer

    - by SalamiArmi
    I have a fictional class: template<typename T> class demonstration { public: demonstration(){} ... T *m_data; } At some point in the program's execution, I want to set m_data to a big block of allocated memory and construct an object T there. At the moment, I've been using this code: void construct() { *m_data = T(); } Which I've now realised is probably not the best idea... wont work under certain cirumstances, if T has a private assignment operator for example. Is there a normal/better way to do what I'm attempting here?

    Read the article

  • Objective-C: Initializing char with char at index of string.

    - by Mr. McPepperNuts
    unichar myChar = [myString characterAtIndex:0]; [myNSMutableArray addObject:myChar]; I am trying to insert the first char of a string into an array, to create an array of chars. the first line does not give me an error. The second line however, provides the following error: warning: passing argument 1 of 'addObject:' makes pointer from integer without a cast This also crashes the application with a "bad address" error. I thought this error was due to a problem with memory allocation. Can someone shed some light on this.

    Read the article

  • Excel workbooks produced by POI don't work when linked

    - by Eric Nicolas
    Here is what I'm doing : Create a workbook in memory (book = new HSSFWorkbook(), ...) Save it to disk (book.write(...)) Open in Excel (ok) Create another workbook in Excel, which links to the first one (=PoiWorkbook?xls!A1) Close Excel Then everytime I open the second workbook again, all the links are #N/A, unless I also open the POI-generated workbook at the same time. I never saw this behaviour with standard workbooks created in Excel. Anyone has seen this and found a workaround ? Thanks.

    Read the article

  • Unit testing with serialization mock objects in C++

    - by lhumongous
    Greetings, I'm fairly new to TDD and ran across a unit test that I'm not entirely sure how to address. Basically, I'm testing a couple of legacy class methods which read/write a binary stream to a file. The class functions take a serializable object as a parameter, which handles the actual reading/writing to the file. For testing this, I was thinking that I would need a serialization mock object that I would pass to this function. My initial thought was to have the mock object hold onto a (char*) which would dynamically allocate memory and memcpy the data. However, it seems like the mock object might be doing too much work, and might be beyond the scope of this particular test. Is my initial approach correct, or can anyone think of another way of correctly testing this? Thanks!

    Read the article

  • how can i set mTextView to show on button click

    - by Ajay Pandey
    i have a UITextView object which i have created in interface builder with it's hidden property unmarked.Now i want this textView to be invisible when my application launches and first view appears.Further i want it to be displayed when a particular method is called.Now this is what i have written in view did load [mTextView setHidden:YES]; self.mTextView=[[UITextView alloc] init]; it hides the textView ats the first view appears but when my desired method is called and i write [mTextView setHidden:NO]; it does not show it again.. Is it like we cant change the appearance of a textView once it is assigned because after assigning memory as self.mTextView=[[UITextView alloc] init]; and then writing [mTextView setHidden:YES]; it does not hide textView in viwDidLoad either.....

    Read the article

  • Output of System.out.println(object)

    - by Shaarad Dalvi
    I want to know what exactly the output tells when I do the following : class data { int a=5; } class main { public static void main(String[] args) { data dObj=new data(); System.out.println(dObj); } } I know it gives something related to object as the output in my case is data@1ae73783. I guess the '1ae73783' is a hex number. I also did some work around and printed System.out.println(dObj.hashCode()); I got number 415360643. I got an integer value. I don't know what hashCode() returns, still out of curiosity, when I converted 1ae73783 to decimal, I got 415360643! That's why I am curious that what exactly is this number?? Is this some memory location of Java's sandbox or some other thing? Any light on this matter will be helpful..thanks! :)

    Read the article

  • Book resources for x86/x64 assembly programming on Win platform

    - by Scott Davies
    Hello, I ran a search for assembly language resources on stackoverflow.com and found some interesting results, but they seemed to boil down to two groups: 1) Assembly references to old ia32 architecture, such as the 80386 to Pentium 2) Windows agnostic books. Most of the commenters make the point that assembler is CPU dependent and that the OS is irrelevant, but it seems pointless to me to pick a book that has assembly examples that refer to MS-DOS interrupts and memory layouts. Likewise, learning assembler on Linux would seem to produce Linux executables Are there any: 1) Modern 2) x86/x64 3) on Windows platform - book resources available ? The reason I am targeting the Win platform is I would like to do low-level, OS internals programming, to supplement my Win C/C++ work. Thanks

    Read the article

  • storing an integer constant other than zero in a pointer variable

    - by benjamin button
    int main() { int *d=0; printf("%d\n",*d); return 0; } this works fine. >cc legal.c > ./a.out 0 if i change the statement int *d=0; to int *d=1; i see the error. cc: "legal.c", line 6: error 1522: Cannot initialize a pointer with an integer constant other than zero. so its obvious that it will allow only zero.i want to know what happens inside the memory when we do this int *d=0 which is making it valid syntax. I am just asking this out of curiosity!

    Read the article

  • How does Photoshop (Or drawing programs) blit?

    - by user146780
    I'm getting ready to make a drawing application in Windows. I'm just wondering, do drawing programs have a memory bitmap which they lock, then set each pixel, then blit? I don't understand how Photoshop can move entire layers without lag or flicker without using hardware acceleration. Also in a program like Expression Design, I could have 200 shapes and move them around all at once with no lag. I'm really wondering how this can be done without GPU help. I don't think super efficient algorithms could justify that? Thanks

    Read the article

  • How do I write raw binary data in Python?

    - by Chris B.
    I've got a Python program that stores and writes data to a file. The data is raw binary data, stored internally as str. I'm writing it out through a utf-8 codec. However, I get UnicodeDecodeError: 'charmap' codec can't decode byte 0x8d in position 25: character maps to <undefined> in the cp1252.py file. This looks to me like Python is trying to interpret the data using the default code page. But it doesn't have a default code page. That's why I'm using str, not unicode. I guess my questions are: How do I represent raw binary data in memory, in Python? When I'm writing raw binary data out through a codec, how do I encode/unencode it?

    Read the article

  • Use of private constructor to prevent instantiation of class?

    - by cringe
    Hi guys! Right now I'm thinking about adding a private constructor to a class that only holds some String constants. public class MyStrings { // I want to add this: private MyString() {} public static final String ONE = "something"; public static final String TWO = "another"; ... } Is there any performance or memory overhead if I add a private constructor to this class to prevent someone to instantiate it? Do you think it's necessary at all or that private constructors for this purpose are a waste of time and code clutter?

    Read the article

  • [CA_COLOR_OPAQUE] things that make a layer non-opaque. scaled CAGradientLayer?

    - by mahal tertin
    i spent some time with the environment variable CA_COLOR_OPAQUE = 1 and have my findings to share. things that make a CALayer non-opaque (slow, more memory, ...): * contents with alpha (like an NSImage with an icon) * NSImage/CGImage from a pdf as contents (even when the pdf does not contain any alpha and opaque=YES) * backgroundColor = nil * CATextLayer with text in a (because it is contents with alpha) * rounded corners? maybe/sometimes * masksToBounds? not necessarily as we scale most of tree with CATransform3DScale on sublayerTransform i found also these rather irritating non-opaque: * CAGradientLayer that is somewhere down in this scaled tree (even when set all the gradient colors without alpha) * edgeAntialiasingMask != 0 of a layer that is somewhere down in this scaled tree the last two do not make sense to me. why should it be non opaque? what do i see? if anyone has any thoughts on these findings, i'm happy to learn as i couldn't find such a list yet.

    Read the article

  • What segments does C compiled program use?

    - by b-gen-jack-o-neill
    Hi, I read on OSDev wiki, that protected mode of x86 architecture allow you to create separate segments for code and data, while you cannot write into code section. That Windows (yes, this is the platform) loads new code into code segment, and data are created on data segment. But, if this is the case, how does program know it must switch segments to the data segment? Becouse if I understand it right, all adress instructions point to the segment you run the code from, unless you switch the descriptor. But I also read, that so colled flat memory model allows you to run code and data within one segment. But I read this only in connection to assembler. So, please, what is the case with C compiled code on Windows? Thanks.

    Read the article

  • Would using a MemoryMappedFile for IPC across AppDomains be faster than WCF/named pipes?

    - by Morten Mertner
    Context: I am loading and executing untrusted code in a separate AppDomain and am currently communicating between the two using WCF (using named pipes as the underlying transport). I am exchanging relatively simple object graphs using a reasonably coarse-grained API, but would like to use a more fine-grained API if it does not cost me performance-wise. I've noticed that 4.0 adds a MemoryMappedFile class (which doesn't need a physical file, so could be entirely memory based). What kind of performance gains could I expect to see (if any) by using this new class? I know that it would take some "infrastructure code" to get the request/response behavior of WCF, but for now I'm only interested in the performance difference.

    Read the article

  • Why does UITableViewCell have a contentView property?

    - by mystify
    What's the point of this contentView property? I mean: Why aren't all the subviews just added to self? Let me get that right: Every cell is a view (UITabvleViewCell is a UIView subclass). And this fat view has another fat view with same bounds sitting on top of it, called contentView. That contentView then carries all those other subviews. Now why didn't they save that extra chunk of memory? Is there any genius logic behind this decision? Would love to understand the reason for this.

    Read the article

  • Get a value from hashtable by a part of its key

    - by htf
    Hi. Say I have a Hashtable<String, Object> with such keys and values: apple => 1 orange => 2 mossberg => 3 I can use the standard get method to get 1 by "apple", but what I want is getting the same value (or a list of values) by a part of the key, for example "ppl". Of course it may yield several results, in this case I want to be able to process each key-value pair. So basically similar to the LIKE '%ppl%' SQL statement, but I don't want to use a (in-memory) database just because I don't want to add unnecessary complexity. What would you recommend?

    Read the article

  • C++ containers on classes, returning pointers

    - by otneil
    Hello, I'm having some trouble to find the best way to accomplish what I have in mind due to my inexperience. I have a class where I need to a vector of objects. So my first question will be: is there any problem having this: vector< AnyType container* and then on the constructor initialize it with new (and deleting it on the destructor)? Another question is: if this vector is going to store objects, shouldn't it be more like vector< AnyTipe* so they could be dynamically created? In that case how would I return an object from a method and how to avoid memory leaks (trying to use only STL)?

    Read the article

  • size of an image

    - by Mike
    From times to times I have to know the width and height of images. I am using the following code: UIImage *imageU = [UIImage imageWithContentsOfFile:[[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"myImage.png"]]; CGFloat imageW = CGImageGetWidth(imageU.CGImage); CGFloat imageH = CGImageGetHeight(imageU.CGImage); My question is that if it is there any other way to know the width and height of an image, in pixels, without having to load the image on a variable, that's probably consuming memory. Can the dimensions be read from the file directly without loading the whole image? thanks.

    Read the article

  • Result of Long Positive Integers & Search and element in array..

    - by AGeek
    Hi, I have two Questions for which I cannot find answers by googling, but I find these questions very important for preparation.. Kindly explain only the logic, I will be able to code. In Search of Efficient Logic..... in terms of Memory and Time. WAP to add two long positive integers. What Data structure / data type we can use to store the numbers and result. What is the best way to search an element from an array in shortest time. Size of the array could be large enough, and any elements could be stored in the array(i.e. no range). Thanks.

    Read the article

  • Retrieving data from an encrypted text file?

    - by user
    Let's say I have a text file contains my data. data : ab bc de - encrypted data on text file : ba cb ed I want to find bc from text file, so I have to decrypt the text file with this code : SL:=TStringList.create; SL.LoadFromFile(textfile) SLtemp:=TStringList.create; for I := 0 to SL.Count - 1 do SLtemp.Add(ReverseString(SL[i])); //decrypt SL.Free; for I := 0 to SLtemp.Count - 1 do if SLtemp[i] = 'bc' then begin showmessage('found'); break; end; SLtemp.Free; I think my way is wasting resources. I have to load whole file to memory and decrypt them. I need some suggestions here to find quickly a specific line from an encrypted text. Thanks.

    Read the article

  • How can I print the cookie_jar values in Perl's WWW::Mechanize?

    - by Phill Pafford
    How can I print the values of the cookie/cookie_jar being set? Trying: ##my $cookie_jar=HTTP::Cookies->new(file => "cookie.jar",autosave=>1,ignore_discard=>1); my $cookie_jar=HTTP::Cookies->new(); ## Would like it to be in memory my $agent = WWW::Mechanize->new(cookie_jar => $cookie_jar); ##my $agent = WWW::Mechanize->new(); ##my $agent = WWW::Mechanize->new(autocheck => 1); ##$agent->cookie_jar( {} ); # we need cookies ##$agent->cookie_jar(HTTP::Cookies->new); print "Set Cookie Jar?\n"; print $agent->cookie_jar->as_string(); print "\n"; $agent->get($url); // url is a https site Not too much luck with any of these, what am I doing wrong?

    Read the article

  • Problem with running a program from flashdrive

    - by rajivpradeep
    I have a USB drive with two partitions in it, one hidden and one normal. I have an application which swaps the memory and runs the flash application in hidden zone. The problem is that the application works fine on Windows 7 and when run on Win XP, it swaps the partitions but doesn't run the flash applications but just keeps running in the background. I can see it in task manager. But, when I copy the application to desktop and run, it runs with no glitch. I was facing the same problem on Win 7 too, but it was running as required when I ran it using "Run in XP mode" and then I applied a SHIM and is running since then as required. The application is built using VC++ 2008. does anyone know the solution?

    Read the article

  • segmentation fault

    - by gcc
    int num_arrays; char *p[20]; char tempc; int i=0; do { p[i]=malloc(sizeof(int)); scanf("%s",p[i]); tempc=p[i]; ++i; }while(tempc=='x'); num_arrays=atoi(p[0]); When i write num_arrays=atoi(..),gcc give me segmentation fault or memory stack is exceeded, I don't understand why it behaves like that can anyone explain, why?

    Read the article

  • Reading file data during form's clean method

    - by Dominic Rodger
    So, I'm working on implementing the answer to my previous question. Here's my model: class Talk(models.Model): title = models.CharField(max_length=200) mp3 = models.FileField(upload_to = u'talks/', max_length=200) Here's my form: class TalkForm(forms.ModelForm): def clean(self): super(TalkForm, self).clean() cleaned_data = self.cleaned_data if u'mp3' in self.files: from mutagen.mp3 import MP3 if hasattr(self.files['mp3'], 'temporary_file_path'): audio = MP3(self.files['mp3'].temporary_file_path()) else: # What goes here? audio = None # setting to None for now ... return cleaned_data class Meta: model = Talk Mutagen needs file-like objects - the first case (where the uploaded file is larger than the size of file handled in memory) works fine, but I don't know how to handle InMemoryUploadedFile that I get otherwise. I've tried: # TypeError (coercing to Unicode: need string or buffer, InMemoryUploadedFile found) audio = MP3(self.files['mp3']) # TypeError (coercing to Unicode: need string or buffer, cStringIO.StringO found) audio = MP3(self.files['mp3'].file) # Hangs seemingly indefinitely audio = MP3(self.files['mp3'].file.read()) Is there something wrong with mutagen, or am I doing it wrong?

    Read the article

< Previous Page | 378 379 380 381 382 383 384 385 386 387 388 389  | Next Page >