Search Results

Search found 16237 results on 650 pages for 'lock free'.

Page 579/650 | < Previous Page | 575 576 577 578 579 580 581 582 583 584 585 586  | Next Page >

• Creating collaborative whiteboard drawing application

  - by Steven Sproat

  I have my own drawing program in place, with a variety of "drawing tools" such as Pen, Eraser, Rectangle, Circle, Select, Text etc. It's made with Python and wxPython. Each tool mentioned above is a class, which all have polymorphic methods, such as left_down(), mouse_motion(), hit_test() etc. The program manages a list of all drawn shapes -- when a user has drawn a shape, it's added to the list. This is used to manage undo/redo operations too. So, I have a decent codebase that I can hook collaborative drawing into. Each shape could be changed to know its owner -- the user who drew it, and to only allow delete/move/rescale operations to be performed on shapes owned by one person. I'm just wondering the best way to develop this. One person in the "session" will have to act as the server, I have no money to offer free central servers. Somehow users will need a way to connect to servers, meaning some kind of "discover servers" browser...or something. How do I broadcast changes made to the application? Drawing in realtime and broadcasting a message on each mouse motion event would be costly in terms of performance and things get worse the more users there are at a given time. Any ideas are welcome, I'm not too sure where to begin with developing this (or even how to test it)

  Read the article

• Deploying DotNetNuke and separate ASP.NET Application together - Possible Issues?

  - by TheTXI

  I am making this in a proactive attempt to head off any potential problems which could arise from this. The situation is that we are developing an ASP.NET application for a client which will handle the online ordering from their customers. This application is going to be using the same database that their current WinForms application uses (no real issue here). At the same time we are developing a new front-end website for them using DotNetNuke. The DotNetNuke app will simply be linking to the ASP.NET application for the customers to submit their orders (no need for them to communicate back and forth, etc.) The plan is to host both applications on the same box at the client location. What I am looking for are potential problems or setup tips which would prevent possible conflict between the two apps (web.config conflicts, etc.) Is there a problem with having both hosted on the same location, how should IIS be set up, etc.? If there are any external resources also available which could address this, please feel free to link them as well.

  Read the article

• Fast, Unicode-capable, cross-platform programmer's text editor that shows invisibles like ZWSP?

  - by Roger_S

  Our publishing workflow includes Windows and Linux machines (there are some Macs too, but not in the critical-path workflow). Many texts include both English and Khmer and are marked-up in XML. XML Copy Editor is the best cross-platform open-source XML editor I've discovered. It utilizes the Scintilla editing component, which is generally good with Unicode but which does not enable non-printing or invisible characters like U+200B (zero-width space) and U+200C (zero-width non-joiner) to be displayed. Khmer does not separate words with a space character as Western languages do, so ZWSP is used in electronic texts to enable applications to break lines easily. Ideally I'd edit the markup and the content in a single editor, but XML awareness is less important at times than being able to display invisibles. (OpenOffice.org Writer and Microsoft Word are the only two apps I know that will display ZWSP. They are not suitable for the markup and text manipulations that need to be done to prepare manuscripts for publication, unfortunately, although I guess they're fine for authoring.) I tried out a promising editor last week, but a search-and-replace regex operation that took under a second in TextPad 4.7.3 lasted over twenty seconds. So I want to mention that speed and the ability to handle large (up to 150mb) files is also a concern. Is there a good, fast, free or not too expensive text editor, with versions on Windows and Linux and maybe mac too, Unicode-aware and capable of displaying invisibles like ZWSP? That has syntax highlighting, can handle large files and is customizable enough that I won't tear my hair out in frustration? Thanks, Roger_S

  Read the article

• jQuery slideDown() Makes Everything in Wrapper Shift

  - by Ben

  Hello everyone, I am currently creating a simple menu where there are several names of services and a user can click on one and jQuery will show it's corresponding paragraph describing it below it. My jQuery code is fine and does exactly what I want, however, I have one bug I have yet to iron out. Whenever I click one of these headings and it's description displays, everything in the wrapper for the page shifts to the left about 7 pixels in Firefox, it does the same thing is Google Chrome however I have not measured the amout but I am sure it is irrelevant. Anyways, I am using the slideToggle() command to show the hidden parragraph. I assume this is occuring because when the slideDown occurs it is somehow changing the width of everything and the "margin: 0 auto;" setting for the wrapper rule in my css is compensating for this change. Does anyone have any way I can remedy this problem? I have tried several other fixes I've found around the internet but to no avail. Here is what my code looks like, I put it on jsFiddle to make it easier to view: http://jsfiddle.net/vcH7m/ Feel free to edit it there if you like, or post what needs to be fixed here. Whatever is more convenient. Thank you very much for the help!

  Read the article

• assembling an object graph without an ORM -- in the service layer or data layer?

  - by Hans Gruber

  At my current gig, our persistence layer uses IBatis going against SQL Server stored procedures (puke). IMHO, this approach has many disadvantages over the use of a "true" ORM such NHibernate or EF, but the one I'm trying to address here revolves around all the boilerplate code needed to map data from a result set into an object graph. Say I have the following DTO object graph I want to return to my presentation layer: IEnumerable<CustomerDTO> |--> IEnumerable<AddressDTO> |--> LatestOrderDTO The way I've implemented this is to have a discrete method in my DAO class to return each IEnumerable<*DTO>, and then have my service class be responsible for orchestrating the calls to the DAO. It then returns the fully assembled object graph to the client: public class SomeService(){ public SomeService(IDao someDao){ this._someDao = someDao; } public IEnumerable<CustomerDTO> ListCustomersForHistory(int brokerId){ var customers = _someDao.ListCustomersForBroker(brokerId); foreach (customer in customers){ customer.Addresses = someDao.ListCustomersAddresses(brokerId); customer.LatestOrder = someDao.GetCustomerLatestOrder(brokerId); } } return customers; } My question is should this logic belong in the service layer or the should I make my DAO such that it instead returns the assembled object graph. If I was using NHibernate, I assume that this kind of relationship association between objects comes for "free"?

  Read the article

• Why does my Android App crash when loading image from gallery the 2nd time?

  - by Sebastian

  Hi folks, I've written an app, thats loading images either using the android gallery app or by taking a photo using the cam. When I now load an image using the gallery, everything is fine. When the code is being executed a second time (for loading another image), the application crashes. try { Uri data = intent.getData(); ContentResolver cr = this.getContentResolver(); Bitmap mBitmap = null; mBitmap = Media.getBitmap(cr, data); imageView.setImageBitmap(mBitmap); } catch(Exception e){ showToast(this, "Failed loading image from gallery"); return; } The code crashes at the line mBimap = Media.getBitmap(cr, data);. Everything is initialized, there are no null values etc. The strange thing is: no exception is thrown, I don't get into the catch block to determine whats going wrong. Does anyone have an idea about this? Am I not allowed to "re-use" the content resolver? Do I have to free it after the first usage or something like this?

  Read the article

• Automated test, build and deploy

  - by mike79

  I have visual studio team suite 2008. I was unable to meet the requirements to setup TFS, so I'm using TortoiseSvn and VisualSvn as my version contol in VSTS. I need the system setup to do the following: I neeed to be able to create and track workitems. When updates are made to the current project worked on in VSTS, the updates will be commited back to version control. Tests will be run to see that updates don't break the application. If there's a problem with the update it will be reported back to the developer. If there's no problem with the app, which is a clickonce application, it will automatically be built and deployed to an ftp server. I've never worked with version control, build servers, automated testing and continous intergration. I need to know what needs to be put in place for this type of system. I don't know which combination/stack I should be using: CC.net, TeamCity, Hudson, NAnt, NUnit, MsTest, Trac, BugTracker.net, Ndepend, VisualSvn Server, Perforce, Msdeploy, SCM. I want something that is free/opensource and relatively easy to setup and use. Please suggest a setup that will fit my needs. Any help appreciated

  Read the article

• how to get selected chracter position in JTextArea?

  - by Reddy

  Hi! Here is a challenging question! Let me first tell you my scenario how am i implementing a solution to a problem. I am reading a log file and displaying it on the JTextArea. Log file is cp037 character coded. I was reading each file as a byte stream or byte array from the log file & displaying it. Anyways, i managed to display the text properly in JTextArea by cp037 character coding. Now, User may select a set of characters in the JTextArea. All i want is the position of first character of the user's selected text, from a nearest special character '+'(its character code in cp037 is 4E), which is prior to the selected text. This character may occur at several places in the JTextArea. In simple sentence, i want the first character location(of user selected text) from nearset '+' which should be occuring prior to the user's selected text. PS: cp037 is a type of character encoding scheme which is created by IBM & used for IBM Mainframes. Please fell free to ask me if the question is not clear...:-

  Read the article

• FORTRAN: Invalid form for an assignment

  - by Sam Goodness

  I can't get this code to compile uding either the g77 minGW compiler or the g95 compiler. Does anyone know why? I get these errors with the g77: diff5z10.for: In subroutine `diffract': diff5z10.for:579: Tropo100 = 20.34 - .077 * Dist ^ Invalid form for assignment statement at (^) diff5z10.for:581: IF (Freq .GT. 1000) FreqAdj = 24.5 - 7200/(Freq+3000) ^ Invalid form for assignment statement at (^) and i get these errors when compiling with g95: In file diff5z10.for:574 CLUTTER = steep*CLUTTER 1 Error: Unclassifiable statement at (1) In file diff5z10.for:580 FreqAdj = 23.978 - 58026.76 / (Freq + 2320) 1 Error: Unclassifiable statement at (1) here is the code from this section of the program: (starting with line 362) Span = .28 - .144 * (Round - 1.2) Para = C / Span**2 IF (Ratio .GT. .4) Para = 6.25 * (C - 1) CLUTTER = Para * (RATIO - .4)**2 - C IF (CLUTTER .GT. 0.) CLUTTER = 0. CSlope = SQRT(freq)/350 steep = 1 + CSlope * (dist - Horizon) IF (steep .LT. 0) steep = 0 IF (steep .GT. 1) steep = 1 CLUTTER = steep*CLUTTER Tropo100 = 20.34 - .077 * Dist FreqAdj = 23.978 - 58026.76 / (Freq + 2320) IF (Freq .GT. 1000) FreqAdj = 24.5 - 7200/(Freq+3000) TropoFd = Tropo100 - FreqAdj FS_field = 106.9 - 20 * LOG10(Dist) Scatter = TropoFd - FS_field !loss ref to free space DiffL = Scatter - DLOSS Combine = 150/(20 - DiffL) - 5 IF (DiffL .LT. -10) Combine = 0 IF (DiffL .GT. 10) Combine = DiffL DLOSS = DLOSS + Combine RETURN END

  Read the article

• If attacker has original data, and encrypted data, can they determine the passphrase?

  - by Brad Cupit

  If an attacker has several distinct items (for example: e-mail addresses) and knows the encrypted value of each item, can the attacker more easily determine the secret passphrase used to encrypt those items? Meaning, can they determine the passphrase without resorting to brute force? This question may sound strange, so let me provide a use-case: User signs up to a site with their e-mail address Server sends that e-mail address a confirmation URL (for example: https://my.app.com/confirmEmailAddress/bill%40yahoo.com) Attacker can guess the confirmation URL and therefore can sign up with someone else's e-mail address, and 'confirm' it without ever having to sign in to that person's e-mail account and see the confirmation URL. This is a problem. Instead of sending the e-mail address plain text in the URL, we'll send it encrypted by a secret passphrase. (I know the attacker could still intercept the e-mail sent by the server, since e-mail are plain text, but bear with me here.) If an attacker then signs up with multiple free e-mail accounts and sees multiple URLs, each with the corresponding encrypted e-mail address, could the attacker more easily determine the passphrase used for encryption? Alternative Solution I could instead send a random number or one-way hash of their e-mail address (plus random salt). This eliminates storing the secret passphrase, but it means I need to store that random number/hash in the database. The original approach above does not require this extra table. I'm leaning towards the the one-way hash + extra table solution, but I still would like to know the answer: does having multiple unencrypted e-mail addresses and their encrypted counterparts make it easier to determine the passphrase used?

  Read the article

• Android Signal 11 (SIGSEGV)

  - by Naturjoghurt

  I read many posts here and on other sites, but can not find the problem creating my Error: I use an AsyncTask because I want to easily manipulate the UI Thread before and after Execution. In doInBackground I create a ThreadPoolExecutor and execute Runnables. If I only execute 1 Runnable with the Executor, there is no Problem, but if I execute another Runnable I get following Error: 06-26 18:00:42.288: A/libc(25073): Fatal signal 11 (SIGSEGV) at 0x7f486162 (code=1), thread 25106 (pool-1-thread-2) 06-26 18:00:42.304: D/dalvikvm(25073): GC_CONCURRENT freed 119K, 2% free 8908K/9056K, paused 4ms+4ms, total 45ms 06-26 18:00:42.327: I/System.out(25073): In Check All with Prefix: a and Length: 4 06-26 18:00:42.390: I/DEBUG(126): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** 06-26 18:00:42.390: I/DEBUG(126): Build fingerprint: 'google/yakju/maguro:4.2.2/JDQ39/573038:user/release-keys' 06-26 18:00:42.390: I/DEBUG(126): Revision: '9' 06-26 18:00:42.390: I/DEBUG(126): pid: 25073, tid: 25106, name: pool-1-thread-2 >>> de.uni_duesseldorf.cn.distributed_computing2 <<< 06-26 18:00:42.390: I/DEBUG(126): signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 7f486162 ... 06-26 18:00:42.538: I/DEBUG(126): memory map around fault addr 7f486162: 06-26 18:00:42.538: I/DEBUG(126): 60292000-60391000 06-26 18:00:42.538: I/DEBUG(126): (no map for address) 06-26 18:00:42.538: I/DEBUG(126): bed14000-bed35000 [stack] I set up the ThreadPoolExecutor like this: // numberOfPackages: Number of Runnables to be executed public void initializeThreadPoolExecutor (int numberOfPackages) { int corePoolSize = Runtime.getRuntime().availableProcessors(); int maxPoolSize = numberOfPackages; long keepAliveTime = 60; final BlockingQueue workingQueue = new LinkedBlockingQueue(); executor = new ThreadPoolExecutor(corePoolSize, maxPoolSize, keepAliveTime, TimeUnit.SECONDS, workingQueue); } I have no clue, why it fails when starting the second Thread. Maybe Memory Leaks? Any Help appreciated. Thanks in Advance

  Read the article

• Using CGContextDrawTiledImage at different zooms causes massive memory growth

  - by Jacques

  I'm working on app an where there's a view in a zoomable UIScrollView. When the user zooms in or out, I redraw the view that's in the UIScrollView to be nice and sharp. That view has a background image that I draw with CGContextDrawTiledImage. I noticed that memory usage grows every time I switch to a new zoom level. It looks like CGContextDrawTiledImage keeps a cache somewhere of the image scaled to different sizes. So, If I go from 1.0 to 1.1x zoom, memory use grows. Going back to 1.0 doesn't cause it to grow, but then going to 1.05 and then 1.2 causes it to grow twice. Back to 1.1 and no growth. Of course, the zoom level is under user control so I don't have control over how many zoom levels happen. Right now my background image is kind of massive (512x512), so this causes memory usage to grow very quickly. It doesn't show up as a memory leak in Instruments, just additional allocations that never get freed. I've tried to find a way to free the cache that appears to be being created, but no luck. It doesn't seem to respond to low memory warnings, for example. I also tried setting the view's backgroundColor to a UIColor created with colorWithPatternImage, but that doesn't work because I'm doing the scaling by changing the graphics context's CTM, not by setting the view's transform. Any ideas on how to keep memory usage from blowing up?

  Read the article

• Query about running a program through valgrind and getting false results comparing to other systems.

  - by FILIaS

  Yesterday i posted this: What's the problem with this code? [hashtable in C] and paxdiablo offered to help me. He posted a sample of code and asked me to run it through valgrind on my machine. This code normally generates: 12,4 But on my machine, i get 24,8. The doubled! I'm just curious why is that happening. Hope sb has a good explaination. I post also paxdiablo's code (for anyone who cant find it.) #include <stdio.h> #include <stdlib.h> typedef struct HashTable { int size ; struct List *head; struct List *tail; } HashTable; typedef struct List { char *number; char *name; int time; struct List *next; } List; #define size_of_table 211 HashTable *createHashTable(void) { HashTable *new_table = malloc(sizeof(*new_table)*size_of_table); //line 606 printf ("%d\n", sizeof(*new_table)); printf ("%d\n", sizeof(new_table)); if (new_table == NULL) { return NULL; } int i=0; for(i; i<size_of_table; i++) { new_table[i].size=0; new_table[i].head=NULL; new_table[i].tail=NULL; } return new_table; } int main(void) { HashTable *x = createHashTable(); free (x); return 0; }

  Read the article

• close file with fopen() but file still in use

  - by Marco

  Hi all, I've got a problem with deleting/overwriting a file using my program which is also being used(read) by my program. The problem seems to be that because of the fact my program is reading data from the file (output.txt) it puts the file in a 'in use' state which makes it impossible to delete or overwrite the file. I don't understand why the file stays 'in use' because I close the file after use with fclose(); this is my code: bool bBool = true while(bBool){ //Run myprogram.exe tot generate (a new) output.txt //Create file pointer and open file FILE* pInputFile = NULL; pInputFile = fopen("output.txt", "r"); // //then I do some reading using fscanf() // //And when I'm done reading I close the file using fclose() fclose(pInputFile); //The next step is deleting the output.txt if( remove( "output.txt" ) == -1 ){ //ERROR }else{ //Succesfull } } I use fclose() to close the file but the file remains in use by my program until my program is totally shut down. What is the solution to free the file so it can be deleted/overwrited? In reality my code isn't a loop without an end ; ) Thanks in advance! Marco

  Read the article

• Finding the width of a directed acyclic graph... with only the ability to find parents

  - by Platinum Azure

  Hi guys, I'm trying to find the width of a directed acyclic graph... as represented by an arbitrarily ordered list of nodes, without even an adjacency list. The graph/list is for a parallel GNU Make-like workflow manager that uses files as its criteria for execution order. Each node has a list of source files and target files. We have a hash table in place so that, given a file name, the node which produces it can be determined. In this way, we can figure out a node's parents by examining the nodes which generate each of its source files using this table. That is the ONLY ability I have at this point, without changing the code severely. The code has been in public use for a while, and the last thing we want to do is to change the structure significantly and have a bad release. And no, we don't have time to test rigorously (I am in an academic environment). Ideally we're hoping we can do this without doing anything more dangerous than adding fields to the node. I'll be posting a community-wiki answer outlining my current approach and its flaws. If anyone wants to edit that, or use it as a starting point, feel free. If there's anything I can do to clarify things, I can answer questions or post code if needed. Thanks! EDIT: For anyone who cares, this will be in C. Yes, I know my pseudocode is in some horribly botched Python look-alike. I'm sort of hoping the language doesn't really matter.

  Read the article

• Simple POSIX threads question

  - by Andy

  Hi, I have this POSIX thread: void subthread(void) { while(!quit_thread) { // do something ... // don't waste cpu cycles if(!quit_thread) usleep(500); } // free resources ... // tell main thread we're done quit_thread = FALSE; } Now I want to terminate subthread() from my main thread. I've tried the following: quit_thread = TRUE; // wait until subthread() has cleaned its resources while(quit_thread); But it does not work! The while() clause does never exit although my subthread clearly sets quit_thread to FALSE after having freed its resources! If I modify my shutdown code like this: quit_thread = TRUE; // wait until subthread() has cleaned its resources while(quit_thread) usleep(10); Then everything is working fine! Could someone explain to me why the first solution does not work and why the version with usleep(10) suddenly works? I know that this is not a pretty solution. I could use semaphores/signals for this but I'd like to learn something about multithreading, so I'd like to know why my first solution doesn't work. Thanks!

  Read the article

• Help C++ifying this C style code.

  - by Flamewires

  Hey I'm used to developing in C and I would like to use C++ in a project. Can anyone give me an example of how I would translate this C-style code into C++ code. I know it should compile in a c++ complier but I'm talking using c++ techniques(I.e. classes, RAII) typedef struct Solution Solution; struct Solution { double x[30]; int itt_found; double value; }; Solution *NewSolution() { Solution *S = (Solution *)malloc(sizeof(Solution)); for (int i=0;<=30;i++) { S-x[i] = 0; } S-itt_found = -1; return S; } void FreeSolution(Solution *S) { if (S != NULL) free(S); } int main() { Solution *S = NewSolution(); S-value = eval(S-x);// evals is another function that returns a double S-itt_found = 0; FreeSolution(S); return EXIT_SUCCESS; } Ideally I would like to be able to so something like this in main, but I'm not sure exactly how to create the class, i've read a lot of stuff but incorporating it all together correctly seems a little hard atm. Solution S(30);//constructor that takes as an argument the size of the double array S.eval();//a method that would run eval on S.x[] and store result in S.value cout << S.value << endl; Ask if you need more info, thanks.

  Read the article

• Cross Platform C library for GUI Apps?

  - by Moshe

  Free of charge, simple to learn/use, Cross Platform C library for GUI Apps? Am I looking for Qt? Bonus question: Can I develop with the said library/toolkit on Mac then recompile on PC/Linux? Super Bonus Question: Link to tutorial and/or download of said library. (RE)EDIT: The truth is that I'm in the process of catching up on the C family (coming from web development - XHTML/PHP/MySQL) to learn iPhone development. I do understand that C is not C++ or ObjectiveC but I want to keep the learning curve as simple as possible. Not to get too off topic, but I am also on the lookout for good starter books and websites. I've found this so far. I'm trying to kill many birds with one stone here. I don understand that there are platform specific extensions, but I will try to avoid those for porting purposes The idea is that I want to write the code on one machine and just compile thrice. (Mac/Win/Linux) If Objective C will compile on Windows and Linux as well as OS X then that's good. If I must use C++, that's also fine. EDIT: Link to QT Please...

  Read the article

• What is the best way to find a processed memory allocations in terms of C# objects

  - by Shantaram

  I have written various C# console based applications, some of them long running some not, which can over time have a large memory foot print. When looking at the windows perofrmance monitor via the task manager, the same question keeps cropping up in my mind; how do I get a break down of the number objects by type that are contributing to this footprint; and which of those are f-reachable and those which aren't and hence can be collected. On numerous occasions I've performed a code inspection to ensure that I am not unnecessarily holding on objects longer than required and disposing of objects with the using construct. I have also recently looked at employing the CG.Collect method when I have released a large number of objects (for example held in a collection which has just been cleared). However, I am not so sure that this made that much difference, so I threw that code away. I am guessing that there are tools in sysinternals suite than can help to resolve these memory type quiestions but I am not sure which and how to use them. The alternative would be to pay for a third party profiling tool such as JetBrains dotTrace; but I need to make sure that I've explored the free options first before going cap in hand to my manager.

  Read the article

• Using Generics to return a literal string or from Dictionary<string, object>

  - by Mike

  I think I outsmarted myself this time. Feel free to edit the title also I could not think of a good one. I am reading from a file and then in that file will be a string because its like an xml file. But in the file will be a literal value or a "command" to get the value from the workContainer so <Email>[email protected]</Email> or <Email>[? MyEmail ?]</Email> What I wanted to do instead of writing ifs all over the place to put it in a generic function so logic is If Container command grab from container else grab string and convert to desired type Its up to the user to ensure the file is ok and the type is correct so another example is so <Answer>3</Answer> or <Answer>[? NumberOfSales ?]</Answer> This is the procedure I started to work on public class WorkContainer:Dictionary<string, object> { public T GetKeyValue<T>(string Parameter) { if (Parameter.StartsWith("[? ")) { string key = Parameter.Replace("[? ", "").Replace(" ?]", ""); if (this.ContainsKey(key)) { return (T)this[key]; } else { // may throw error for value types return default(T); } } else { // Does not Compile if (typeof(T) is string) { return Parameter } // OR return (T)Parameter } } } The Call would be mail.To = container.GetKeyValue<string>("[email protected]"); or mail.To = container.GetKeyValue<string>("[? MyEmail ?]"); int answer = container.GetKeyValue<int>("3"); or answer = container.GetKeyValue<int>("[? NumberOfSales ?]"); But it does not compile?

  Read the article

• Three most critical programming concepts

  - by Todd

  I know this has probably been asked in one form or fashion but I wanted to pose it once again within the context of my situation (and probably others here @ SO). I made a career change to Software Engineering some time ago without having an undergrad or grad degree in CS. I've supplemented my undergrad and grad studies in business with programming courses (VB, Java,C, C#) but never performed academic coursework in the other related disciplines (algorithms, design patterns, discrete math, etc.)...just mostly self-study. I know there are several of you who have either performed interviews and/or made hiring decisions. Given recent trends in demand, what would you say are the three most essential Comp Sci concepts that a developer should have a solid grasp of outside of language syntax? For example, I've seen blog posts of the "Absolute minimum X that every programmer must know" variety...that's what I'm looking for. Again if it's truly a redundancy please feel free to close; my feelings won't be hurt. (Closest ones I could find were http://stackoverflow.com/questions/164048/basic-programming-algorithmic-concepts- which was geared towards a true beginner, and http://stackoverflow.com/questions/648595/essential-areas-of-knowledge-which I didn't feel was concrete enough). Thanks in advance all! T.

  Read the article

• Where can I get software-related legal advice?

  - by musicfreak

  Whenever someone asks a legal question here on SO, the response is usually something along the lines of "we are not lawyers." Okay, that's legitimate, but in that case, how can I talk to a lawyer about software-related legal matters? I could look through the phone book and find a local lawyer, but then I have no way of knowing whether the lawyer knows anything about software. (And I hear most local lawyers charge for your time, even if it's just a simple question.) Is there maybe some kind of online service for this sort of thing? For now, I'm just looking for some basic advice, so something free would be awesome, even if the "quality" is not as good. However, I'll still take any kind of paid services--I'll keep them in mind for the future. You can give me anything from a forum or QA site (like this one) to a professional service. Just remember that I'm looking specifically for software-related legal advice. I'm sure most lawyers know a thing or two about software, but I'd rather talk to someone who legitimately knows his stuff than someone who can only guess.

  Read the article

• C++ design related question

  - by Kotti

  Hi! Here is the question's plot: suppose I have some abstract classes for objects, let's call it Object. It's definition would include 2D position and dimensions. Let it also have some virtual void Render(Backend& backend) const = 0 method used for rendering. Now I specialize my inheritance tree and add Rectangle and Ellipse class. Guess they won't have their own properties, but they will have their own virtual void Render method. Let's say I implemented these methods, so that Render for Rectangle actually draws some rectangle, and the same for ellipse. Now, I add some object called Plane, which is defined as class Plane : public Rectangle and has a private member of std::vector<Object*> plane_objects; Right after that I add a method to add some object to my plane. And here comes the question. If I design this method as void AddObject(Object& object) I would face trouble like I won't be able to call virtual functions, because I would have to do something like plane_objects.push_back(new Object(object)); and this should be push_back(new Rectangle(object)) for rectangles and new Circle(...) for circles. If I implement this method as void AddObject(Object* object), it looks good, but then somewhere else this means making call like plane.AddObject(new Rectangle(params)); and this is generally a mess because then it's not clear which part of my program should free the allocated memory. ["when destroying the plane? why? are we sure that calls to AddObject were only done as AddObject(new something).] I guess the problems caused by using the second approach could be solved using smart pointers, but I am sure there have to be something better. Any ideas?

  Read the article

• visual studio 2008 (VB)

  - by Ousman

  hello guys, Am writing a programming with visual basic 2008 and i want the programme to be able to read and loop through a text file line by line and showing the event of the loop on a textbox or label until a button is press and the loop will stop on any number that happend to be at the loop event and when a button is press again the loop will continue from where it starts. this is my codes below and having problem with it and any help will be really great. tanks ==========================my codes======================= Imports System.IO '========================================================================================== Public Class Form1 '====================================================================================== 'Dim nFileNum As Integer = FreeFile() ' Get a free file number Dim strFileName As String = "C:\scb.txt" Dim objFilename As FileStream = New FileStream(strFileName, FileMode.Open, FileAccess.Read, FileShare.Read) Dim objFileRead As StreamReader = New StreamReader(objFilename) 'Dim lLineCount As Long 'Dim sNextLine As String '====================================================================================== '======================================================================================== Private Sub btStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btStart.Click Try If objFileRead.ReadLine = Nothing Then MsgBox("No Accounts Available to show!", MsgBoxStyle.Information, MsgBoxStyle.DefaultButton2 = MsgBoxStyle.OkOnly) Return Else Do While (objFileRead.Peek() > -1) Loop lblAccounts.Text = objFileRead.ReadLine() 'objFileRead.Close() 'objFilename.Close() End If Catch ex As Exception MessageBox.Show(ex.Message) Finally 'objFileRead.Close() 'objFilename.Close() End Try End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load End Sub End Class

  Read the article

• C++ Suppress Automatic Initialization and Destruction

  - by Travis G

  How does one suppress the automatic initialization and destruction of a type? While it is wonderful that T buffer[100] automatically initializes all the elements of buffer, and destroys them when they fall out of scope, this is not the behavior I want. #include <iostream> static int created = 0, destroyed = 0; struct S { S() { ++created; } ~S() { ++destroyed; } }; template <typename T, size_t KCount> class Array { private: T m_buffer[KCount]; public: Array() { // some way to suppress the automatic initialization of m_buffer } ~Array() { // some way to suppress the automatic destruction of m_buffer } }; int main() { { Array<S, 100> arr; } std::cout << "Created:\t" << created << std::endl; std::cout << "Destroyed:\t" << destroyed << std::endl; return 0; } The output of this program is: Created: 100 Destroyed: 100 I would like it to be: Created: 0 Destroyed: 0 My only idea is to make m_buffer some trivially constructed and destructed type like char and then rely on operator[] to wrap the pointer math for me, although this seems like a horribly hacked solution. Another solution would be to use malloc and free, but that gives a level of indirection that I do not want.

  Read the article

< Previous Page | 575 576 577 578 579 580 581 582 583 584 585 586  | Next Page >