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• Upgrade issues due to broken "dependency problems prevent configuration of linux-image-generic" error

  - by tsukune1791

  okay, I've recently upgrade from 11.10 to 12.04 and I've been having some issues. I don't know if its a bug or not, but I thought I would submit it here. Okay here's a little background; I ran the distro update from the update manager and got a couple errors that I didn't catch. the computer restarted, and when I logged the Launcher and my top bar of the Ubuntu desktop didn't load. While it was trying to load a couple error messages came up, I think they were called "apport", saying they couldn't send the bug information for some reason. I believe it said somethings wrong with my internet connection, but nothing's wrong with it. Anyway I tried running some things in terminal, namely sudo apt-get -f install sudo apt-get upgrade sudo apt-get dist-upgrade and keep getting the following errors; dustin@marceau-laptop:~$ sudo apt-get dist-upgrade [sudo] password for dustin: Reading package lists... Done Building dependency tree Reading state information... Done Calculating upgrade... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. 4 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Do you want to continue [Y/n]? Y Setting up initramfs-tools (0.99ubuntu13) ... update-initramfs: deferring update (trigger activated) Setting up linux-image-3.2.0-24-generic (3.2.0-24.37) ... Running depmod. update-initramfs: deferring update (hook will be called later) Examining /etc/kernel/postinst.d. run-parts: executing /etc/kernel/postinst.d/dkms 3.2.0-24-generic /boot/vmlinuz-3.2.0-24-generic run-parts: executing /etc/kernel/postinst.d/initramfs-tools 3.2.0-24-generic /boot/vmlinuz-3.2.0-24-generic update-initramfs: Generating /boot/initrd.img-3.2.0-24-generic run-parts: executing /etc/kernel/postinst.d/pm-utils 3.2.0-24-generic /boot/vmlinuz-3.2.0-24-generic run-parts: executing /etc/kernel/postinst.d/update-notifier 3.2.0-24-generic /boot/vmlinuz-3.2.0-24-generic run-parts: executing /etc/kernel/postinst.d/zz-runlilo 3.2.0-24-generic /boot/vmlinuz-3.2.0-24-generic Fatal: No images have been defined. run-parts: /etc/kernel/postinst.d/zz-runlilo exited with return code 1 Failed to process /etc/kernel/postinst.d at /var/lib/dpkg/info/linux-image-3.2.0-24-generic.postinst line 1010. dpkg: error processing linux-image-3.2.0-24-generic (--configure): subprocess installed post-installation script returned error exit status 2 dpkg: dependency problems prevent configuration of linux-image-generic: linux-image-generic depends on linux-image-3.2.0-24-generic; however: Package linux-image-3.2.0-24-generic is not configured yet. dpkg: error processing linux-image-generic (--configure): dependency problems - leaving unconfigured dpkg: dependency problems prevent configuration of linux-generic: linux-generic depends on linux-image-generic (= 3.2.0.24.26); however: Package linux-image-generic is not configured yet. dpkg: error processing linux-generic (--configure): dependency problems - leaving unconfigured Processing triggers for initramfs-tools ... No apport report written because the error message indicates its a followup error from a previous failure. No apport report written because the error message indicates its a followup error from a previous failure. update-initramfs: Generating /boot/initrd.img-3.2.0-24-generic Fatal: No images have been defined. run-parts: /etc/initramfs/post-update.d//runlilo exited with return code 1 dpkg: error processing initramfs-tools (--configure): subprocess installed post-installation script returned error exit status 1 No apport report written because MaxReports is reached already Errors were encountered while processing: linux-image-3.2.0-24-generic linux-image-generic linux-generic initramfs-tools localepurge: Disk space freed in /usr/share/locale: 0 KiB localepurge: Disk space freed in /usr/share/man: 0 KiB localepurge: Disk space freed in /usr/share/gnome/help: 0 KiB localepurge: Disk space freed in /usr/share/omf: 0 KiB localepurge: Disk space freed in /usr/share/doc/kde/HTML: 0 KiB Total disk space freed by localepurge: 0 KiB E: Sub-process /usr/bin/dpkg returned an error code (1) And my Ubuntu desktop is still not working. I can log into Gnome and Ubuntu 2D but the Launcher, I think it's call, doesn't load. Can someone help me fix these error, or point me in the right direction to get them fixed? It is much appriciated.

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• Broken Sudo - sudo: parse error in /etc/sudoers near line 23

  - by Robert Fáber

  I am getting this error: sudo: parse error in /etc/sudoers near line 23 sudo: no valid sudoers sources found, quitting sudo: unable to initialize policy plugin I was trying to disable password authentication so I don't have to type password every time I want to install something, but I probably changed it in a not very good way. I am a newbie to Ubuntu, I got sick of Windows :) So far I've found some people suggesting booting in single user mode, but I'm afraid of messing things up more.

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• Sprites, Primitives and logic entity as structs

  - by Jeffrey

  I'm wondering would it be considered acceptable: The window class is responsible for drawing data, so it will have a method: Window::draw(const Sprite&); Window::draw(const Rect&); Window::draw(const Triangle&); Window::draw(const Circle&); and all those primitives + sprites would be just public struct. For example Sprite: struct Sprite { float x, y; // center float origin_x, origin_y; float width, height; float rotation; float scaling; GLuint texture; Sprite(float w, float h); Sprite(float w, float h, float a, float b); void useTexture(std::string file); void setOrigin(float a, float b); void move(float a, float b); // relative move void moveTo(float a, float b); // absolute move void rotate(float a); // relative rotation void rotateTo(float a); // absolute rotation void rotationReset(); void scale(float a); // relative scaling void scaleTo(float a); // absolute scaling void scaleReset(); }; So instead of having each primitive to call their draw() function, which is a little bit off topic for their object, I let the Window class handle all the OpenGL stuff and manipulate them as simple objects that will be drawn later on. Is this pattern used? Does it have any cons against it's primitives-draw-themself pattern? Are there any other related patterns?

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• Broken BURG install after backup/restore

  - by WindowsEscapist

  Long story short: BURG is stuck in text mode and I can't seem to get it back to the eye-candy. I have purged and then re-installed to no avail. I am running 12.04. The long story: I originally installed onto 12.04 using Super-boot-manager (BURG-manager) and then stopped using it in favour of GRUB because I had too many entries. I then had to backup and restore Ubuntu (partition was deleted and re-created) due to unrelated issues. I re-installed GRUB2 and booted into Ubuntu to re-install BURG, but after re-booting it appears to be stuck in text mode (looks exactly like GRUB 1). Any ideas? I know I'm not supposed to be using it on 12.04 (I think) but it worked before, so what's up?

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• ZFS pool broken after upgrading to 14.04 LTS

  - by cruiserparts

  Well, I have been putting off upgrading to 14.04 for fear that I would break something. Actually for fear that it would break zfs (or I would break it). I am bascially slightly better than novice at linux. Spent the last couple of hours trying to get the pool back. Now I am at the stage where I don't think I have a complete failure, but I am worried that I may break it. So if could help me not break it, and recover it, I would be thankful. My zfs is file storage and not boot. It was working fine for a year and was working perfectly before the upgrade (scrub and everything was fine). I was confident that the upgrade would work (or at least I could fix it) because I had upgraded once in the past, the pool went missing, but I was able to get it back. I have reinstalled zfs, zfs utilities, and some dependencies (after searching this forum) I think what happened is 14.04 deleted some config file, or specified disk names differntly, but I could be wrong. When I set the pool up originally, I was using specific device Ids as I recall (because I did not want to break things if they got reassigned at boot) So see if this helps. I can confirm that old mountpoint folders are there but empty. no talloc stackframe at ../source3/param/loadparm.c:4864, leaking memory pool: naspool1 state: UNAVAIL status: One or more devices could not be used because the label is missing or invalid. There are insufficient replicas for the pool to continue functioning. action: Destroy and re-create the pool from a backup source. see: http://zfsonlinux.org/msg/ZFS-8000-5E scan: none requested config: NAME STATE READ WRITE CKSUM naspool1 UNAVAIL 0 0 0 insufficient replicas raidz1-0 UNAVAIL 0 0 0 insufficient replicas scsi-SATA_WDC_WD1001FALS-_WD-WMATV0990825 UNAVAIL 0 0 0 scsi-SATA_WDC_WD1001FALS-_WD-WMATV2995365 UNAVAIL 0 0 0 scsi-SATA_WDC_WD10EARS-00_WD-WMAV51894349 UNAVAIL 0 0 0 ___@ourserver:~$ sudo zpool import naspool1 cannot import 'naspool1': a pool with that name is already created/imported, and no additional pools with that name were found ___@ourserver:~$ sudo zfs list no datasets available What other output can I post to help? I'm thinking the update deleted some zfs config files. It seems like the pool exists and certainly 3 perfectly working disks did not fail at once. I am worried that I may break something without a little bit of guideance. Thanks.

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• Hamster Time Tracker Broken After Upgrade to 11.10

  - by Michael Robinson

  After upgrading 11.04 to 11.10 (which was rather bumpy because of a failure with the flash-installer), I can't seem to start hamster-time-tracker. Output: user@machine:~$ hamster-time-tracker Traceback (most recent call last): File "/usr/bin/hamster-time-tracker", line 478, in <module> from hamster import i18n ImportError: cannot import name i18n Does anyone have any tips on where to start with this issue?

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• Math > Logic for a Logarithmic Score Meter

  - by oodavid

  I'm trying to implement a score meter whereby I specify a maximum value (say 15,000) and I can render values on it in a logarithmic manner ie: +------+---+--+-++ +------+---+--+-++ |== | |====== | +------+---+--+-++ +------+---+--+-++ 200 pts 1,000 pts +------+---+--+-++ +------+---+--+-++ |============= | |================| +------+---+--+-++ +------+---+--+-++ 5,000 pts 15,000 pts + The upper bound needs to be variable, and need to be able to convert a score to a percentage, using the above mockup as an example: score2pct(15000, 200) = 0.2 score2pct(15000, 1000) = 0.4 score2pct(15000, 5000) = 0.8 score2pct(15000, 15000) = 1 Does anyone have any pointers for me?

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• Broken links in content reports when tracking subdomains with Google Analytics

  - by Rob Sobers

  I have a tracking code that I use on my main site and my blog, which is on a subdomain: www.example.com blog.example.com I have a single profile in Google Analytics. I use advanced segments to look at traffic to the main site vs. traffic to the blog. Problem 1: When I'm browsing my content reports under Standard Reporting, the "Page" column doesn't show the top-level or sub-domain, so I can't differentiate www.example.com/index.html from blog.example.com/index.html easily. According to the docs, this filter is supposed to make GA prepend the hostname to the page URL in your content reports, but it doesn't seem to work. Problem 2: When I click on the little "Open in new window" icon next to a given page in a content report line, it always assumes the page lives on www.example.com, so I get 404s when the page is actually on blog.example.com. Is there a good solution for these subdomain tracking problems?

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• Samsung 700Z broken by Precise install

  - by Eric

  I tried to install Precise from DVD media and got to the point where the Ubuntu logo is on screen indicating the the installer is loading. At that point the screen went dark. After some time I rebooted the machine. To my dismay the machine would no longer start (Powers on but but no bios start up screen, I can hear initial hard drive spin which soon dies). This is a new machine (less than 2 months) and I have had no previous indications of defects before this incident. In other words, I am convinced the Ubuntu install had something to do with the failure of the machine. Has anyone else had this problem with this model machine? Is this known to happen with precise or other versions of Ubuntu?

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• System broken after installing Gtk+-3.4.1 with broadway backend enabled

  - by Roman D. Boiko

  I am running Ubuntu 11.10 from VirtualBox. I installed Gtk+ 3.4.1 (latest stable release) from sources with X11 and broadway backends enabled. In order to do that, I also installed latest versions of glib, libffi, libtiff, libjped, gdk-pixbuf, and pango. Each of them was configured with default options. I.e., they were installed to /usr/local (at least, I see respective folders in /usr/local/include). After reboot and login (regardless which user), desktop is grey for about 30 sec, nothing is displayed. Then Nautilus starts, but nothing else (my locale is Ukrainian, but there is nothing important in text): . During boot, I can access command prompt as root, use dpkg, etc. But I don't know what to do. One idea is to reinstall Gtk+ and other libraries with prefix /usr or /usr/shared. I will try that, but it is quite time-consuming, so any ideas would be welcome. Reverting to earlier snapshot is still possible, but it is 6 days old and I would like to try to solve the problem.

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• Object inheritance and method parameters/return types - Please check my logic

  - by user2368481

  I'm preparing for a test and doing practice questions, this one in particular I am unsure I did correctly: We are given a very simple UML diagram to demonstrate inheritance: I hope this is clear, it shows that W inherits from V and so on: |-----Y V <|----- W<|-----| |-----X<|----Z and this code: public X method1(){....} method2(new Y()); method2(method1()); method2(method3()); The questions and my answers: Q: What types of objects could method1 actually return? A: X and Z, since the method definition includes X as the return type and since Z is a kind of X is would be OK to return either. Q: What could the parameter type of method2 be? A: Since method2 in the code accepts Y, X and Z (as the return from method1), the parameter type must be either V or W, as Y,X and Z inherit from both of these. Q: What could return type of method3 be? A: Return type of method3 must be V or W as this would be consistent with answer 2.

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• Debugging a Broken Stylesheet: CSS Background Disappears when Scroll Off Bottom of Screen

  - by nannette

  I recently worked on an existing project where we decided to add a background to the site. Whether this is a background color or background image, the same problem occured. The problem was that the background loaded fine in the screen. But when the user used the scrollbar to scroll below the bottom edge of the screen, the background immediately turned white. The footer panel was colorized as desired, but the background just disappeared. I'm going to provide my debugging steps so you can learn how...(read more)

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• xvkbd broken with warnings

  - by Maxrunner

  Im using the latest version of ubunto and i cant run xvkbd properly, i get these errors: $ xvkbd Warning: Cannot convert string "--lucidatypewriter-bold-r--*-12---*---iso8859-1" to type FontStruct xvkbd: Mode_switch not available as a modifier xvkbd: although ISO_Level3_Shift is used instead, AltGr may not work correctly Warning: Cannot convert string "--lucida-bold-i--*-14---*---iso8859-1" to type FontStruct xvkbd: Mode_switch not available as a modifier xvkbd: although ISO_Level3_Shift is used instead, AltGr may not work correctly how can i solve this?, im trying to use this with xbindkeys.

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• Designing and refactoring of payment logic

  - by jokklan

  Im currently working on an application that helps users to coordinate dinner clubs and all related accounting. (A dinner club is where people in a group, take turns to cook for the rest and then you pay a small amount to participate. This is pretty normal in dorms and colleges where im from). However there is some different models that all have a price and the accounting aspect is therefore a little spread. We both have DinnerClub, ShoppingItem and are about to implement the third Payment when users pay their debts (or get refunded for expenses). Each of these have a "price" attribute and a users expense (that he or she needs refunded) is calculated by the total of these "prices" minus what other users have bought and he or she have used/participated in. My question is then if someone have some hints to refactor this bring all this behavior together in one place? For now have i thought about a Transaction class that are responsible for this behaviour, but I'm a little worried about the performance impact on having to query for another polymorphic record each time i want to show the price on dinner clubs and shopping items (i have a standard index page with a list for both so it's a lot of extra records being queried)...

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• Data breakpoints to find points where data gets broken

  - by raccoon_tim

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

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• Apt-Daemon problem due to a broken sun-java6-jre package

  - by Marv

  I am having problems with installation with everything in the software center. Traceback (most recent call last): File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 968, in simulate trans.unauthenticated = self._simulate_helper(trans) File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 1092, in _simulate_helper return depends, self._cache.required_download, \ File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 235, in required_download pm.get_archives(fetcher, self._list, self._records) SystemError: E:I wasn't able to locate a file for the sun-java6-jre package. This might mean you need to manually fix this package. Help?

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• Reporting Solution in PHP / CodeIgniter - Server side logic vs client side

  - by dot

  I'm building a report for an end user. They would like to see a list of all widgets... but then also like to see widgets with missing attributes, like missing names, or missing size. So i was thinking of creating one method that returns json data containing all widgets... and then using javascript to let them filter the data for missing data, instead of requerying the database. Ultimately, they need to be able to save all "reports" (filtered versions of data) inside a csv file. These are the two options I'm mulling over: Design 1 Create 3 separate methods in my controller/model like: get_all_data() get_records_with_missing_names() get_records_with_missing_size() And then when these methods are called, I would display the data on screen and give them a button to save to csv file. Design 2 Create one method called get_all_data() and then somehow, give them tools in the view to filter the json data using tables etc... and then letting them save subsets of the data. The reality is, in order to display all data, I still need to massage the data, and therefore, I know which records are missing attributes. So i'd rather not create separate methods by each filter. I'm not sure how I would do that just yet but at this point, i would like to know some pros/cons of each method. Thanks.

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• Wubi installation broken by update - now unable to mount

  - by Outspaced

  As of today, my wubi installation of Ubuntu won't boot (goes straight to 'minimal bash-like interface) and I am unable to mount it when I boot straight to Ubuntu. If I boot straight into Ubuntu (not using Wubi, not going via Windows), I am able to mount the Windows partition and see the Wubi partition there: sudo mount -t ntfs /dev/sda5 /media/winxp And from there I can see the wubi root disk: /media/winxp/ubuntu/disks/root.disk But if I try to mount this: sudo mount -o loop /media/winxp/ubuntu/disks/root.disk /media/wubi I get an error: /media/winxp/ubuntu/disks/root.disk Input/Output Error If I then try fsck: sudo fsck /media/winxp/ubuntu/disks/root.disk I get this: Input/Output Error while trying to open /media/winxp/ubuntu/disks/root.disk The Superblock could not be read or does not describe a correct etx2 filesystem. If the device is valid and it really contains an ext2 filesystem (and not swap or ufs or something else), then the superblock is corrupt and you might want to try running e2fsk with an alternate superblock: e2fsck -b 8193 <device ... this gives me the same result. There is data on this partition that I really need to be able to access, so I can't delete and reinstall. Any help much appreciated. Thanks.

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• Handle all authentication logic in database or code?

  - by Snuffleupagus

  We're starting a new(ish) project at work that has been handed off to me. A lot of the database sided stuff has been fleshed out, including some stored procedures. One of the stored procedures, for example, handles creation of a new user. All of the data is validated in the stored procedure (for example, password must be at least 8 characters long, must contain numbers, etc) and other things, such as hashing the password, is done in the database as well. Is it normal/right for everything to be handled in the stored procedure instead of the application itself? It's nice that any application can use the stored procedure and have the same validation, but the application should have a standard framework/API function that solves the same problem. I also feel like it takes away the data from the application and is going to be harder to maintain/add new features to.

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• Broken package ubuntuone-control-panel-qt

  - by baale7

  An interrupted installation of updates resulted in ubuntuone-control-panel-qt breaking and now I cannot install or update anything. There seems to be an error in python2.7 - ImportError: No module named _sysconfigdata_nd dpkg: error processing archive ubuntuone-control-panel-qt_13.09-0ubuntu1_all.deb (--install): When I try to reinstall the package via .deb a dpkg --audit yields: The following packages are in a mess due to serious problems during installation. They must be reinstalled for them (and any packages that depend on them) to function properly: ?python-pexpect Python module for automating interactive applications ?ubuntuone-control-panel-qt Ubuntu One Control Panel - Qt frontend ?hplip-data HP Linux Printing and Imaging - data files ?python-libxml2 Python bindings for the GNOME XML library ?apport automatically generate crash reports for debugging The following packages are only half configured, probably due to problems configuring them the first time. The configuration should be retried using dpkg --configure or the configure menu option in dselect: ?python-ubuntuone-client Ubuntu One client Python libraries ?python-ubuntuone-control-panel Ubuntu One Control Panel - Python Libraries --configure or --configure -a doesn't work Any help?

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• Seperation of drawing and logic in games

  - by BFree

  I'm a developer that's just now starting to mess around with game development. I'm a .Net guy, so I've messed with XNA and am now playing around with Cocos2d for the iPhone. My question really is more general though. Let's say I'm building a simple Pong game. I'd have a Ball class and a Paddle class. Coming from the business world development, my first instinct is to not have any drawing or input handling code in either of these classes. //pseudo code class Ball { Vector2D position; Vector2D velocity; Color color; void Move(){} } Nothing in the ball class handles input, or deals with drawing. I'd then have another class, my Game class, or my Scene.m (in Cocos2D) which would new up the Ball, and during the game loop, it would manipulate the ball as needed. The thing is though, in many tutorials for both XNA and Cocos2D, I see a pattern like this: //pseudo code class Ball : SomeUpdatableComponent { Vector2D position; Vector2D velocity; Color color; void Update(){} void Draw(){} void HandleInput(){} } My question is, is this right? Is this the pattern that people use in game development? It somehow goes against everything I'm used to, to have my Ball class do everything. Furthermore, in this second example, where my Ball knows how to move around, how would I handle collision detection with the Paddle? Would the Ball need to have knowledge of the Paddle? In my first example, the Game class would have references to both the Ball and the Paddle, and then ship both of those off to some CollisionDetection manager or something, but how do I deal with the complexity of various components, if each individual component does everything themselves? (I hope I'm making sense.....)

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• Broken Views

  - by Ajarn Mark Caldwell

  “SELECT *” isn’t just hazardous to performance, it can actually return blatantly wrong information. There are a number of blog posts and articles out there that actively discourage the use of the SELECT * FROM …syntax.  The two most common explanations that I have seen are: Performance:  The SELECT * syntax will return every column in the table, but frequently you really only need a few of the columns, and so by using SELECT * your are retrieving large volumes of data that you don’t need, but the system has to process, marshal across tiers, and so on.  It would be much more efficient to only select the specific columns that you need. Future-proof:  If you are taking other shortcuts in your code, along with using SELECT *, you are setting yourself up for trouble down the road when enhancements are made to the system.  For example, if you use SELECT * to return results from a table into a DataTable in .NET, and then reference columns positionally (e.g. myDataRow[5]) you could end up with bad data if someone happens to add a column into position 3 and skewing all the remaining columns’ ordinal position.  Or if you use INSERT…SELECT * then you will likely run into errors when a new column is added to the source table in any position. And if you use SELECT * in the definition of a view, you will run into a variation of the future-proof problem mentioned above.  One of the guys on my team, Mike Byther, ran across this in a project we were doing, but fortunately he caught it while we were still in development.  I asked him to put together a test to prove that this was related to the use of SELECT * and not some other anomaly.  I’ll walk you through the test script so you can see for yourself what happens. We are going to create a table and two views that are based on that table, one of them uses SELECT * and the other explicitly lists the column names.  The script to create these objects is listed below. IF OBJECT_ID('testtab') IS NOT NULL DROP TABLE testtabgoIF OBJECT_ID('testtab_vw') IS NOT NULL DROP VIEW testtab_vwgo IF OBJECT_ID('testtab_vw_named') IS NOT NULL DROP VIEW testtab_vw_namedgo CREATE TABLE testtab (col1 NVARCHAR(5) null, col2 NVARCHAR(5) null)INSERT INTO testtab(col1, col2)VALUES ('A','B'), ('A','B')GOCREATE VIEW testtab_vw AS SELECT * FROM testtabGOCREATE VIEW testtab_vw_named AS SELECT col1, col2 FROM testtabgo Now, to prove that the two views currently return equivalent results, select from them. SELECT 'star', col1, col2 FROM testtab_vwSELECT 'named', col1, col2 FROM testtab_vw_named OK, so far, so good.  Now, what happens if someone makes a change to the definition of the underlying table, and that change results in a new column being inserted between the two existing columns?  (Side note, I normally prefer to append new columns to the end of the table definition, but some people like to keep their columns alphabetized, and for clarity for later people reviewing the schema, it may make sense to group certain columns together.  Whatever the reason, it sometimes happens, and you need to protect yourself and your code from the repercussions.) DROP TABLE testtabgoCREATE TABLE testtab (col1 NVARCHAR(5) null, col3 NVARCHAR(5) NULL, col2 NVARCHAR(5) null)INSERT INTO testtab(col1, col3, col2)VALUES ('A','C','B'), ('A','C','B')goSELECT 'star', col1, col2 FROM testtab_vwSELECT 'named', col1, col2 FROM testtab_vw_named I would have expected that the view using SELECT * in its definition would essentially pass-through the column name and still retrieve the correct data, but that is not what happens.  When you run our two select statements again, you see that the View that is based on SELECT * actually retrieves the data based on the ordinal position of the columns at the time that the view was created.  Sure, one work-around is to recreate the View, but you can’t really count on other developers to know the dependencies you have built-in, and they won’t necessarily recreate the view when they refactor the table. I am sure that there are reasons and justifications for why Views behave this way, but I find it particularly disturbing that you can have code asking for col2, but actually be receiving data from col3.  By the way, for the record, this entire scenario and accompanying test script apply to SQL Server 2008 R2 with Service Pack 1. So, let the developer beware…know what assumptions are in effect around your code, and keep on discouraging people from using SELECT * syntax in anything but the simplest of ad-hoc queries. And of course, let’s clean up after ourselves.  To eliminate the database objects created during this test, run the following commands. DROP TABLE testtabDROP VIEW testtab_vwDROP VIEW testtab_vw_named

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• BURG broken by Windows

  - by Sallée

  I have successfully installed, using Super Boot Manager, BURG in a computer at my work. After I boot into Windows XP, BURG is no longer operational. The machine just boots to the BIOS screen, goes black, and then boots to the BIOS screen again ad infinitum. The only way to recover I have found so far is to use a Boot-Repair USB, which restores either GRUB2 or MBR, not BURG. Everything works fine under GRUB2, but I prefer the improved look of BURG to make things easier on my students.

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• Latest alestic ec2 Ubuntu instance seems broken

  - by Kave

  I am using alestic.com ec2 Ubuntu instances now for some time and never had a problem with. Today I created a new Ubuntu 12.04 LTS Precise EBS boot on US-east-1, seems to be a bad build. While doing a sudo apt-get update it breaks and says: W: Failed to fetch bzip2:/var/lib/apt/lists/partial/us-east-1.ec2.archive.ubuntu.com_ubuntu_dists_precise-updates_main_source_Sources Hash Sum mismatch This is on a fresh instance. So I recon something went wrong when creating it. What can be done to fix it?

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• design an extendible and pluggable business logic flow handler in php

  - by Broncha

  I am working on a project where I need to allow a pluggable way to inject business processes in the normal data flow. eg There is an ordering system. The standard flow of the application is A consumer orders an item. Pays for it and card is authorized. Admin captures the payment. Order is marked as complete and item is shipped. But this process may vary (extra steps in between) for different clients. Say a client would need to validate the location of the consumer before he is presented with a credit card form, OR his policies might require some other processes in between. I am thinking of using State Pattern for processing orders, saving the current state of the order in database, and initializing the state of order from the saved state. I would also need some mechanism, where a small plugin would be able to inject business specific states in the state machine. Am I thinking the right way? Are there already implemented patterns for this kind of situation? I am working with Codeigniter and basically this would mean for me, to redirect to proper controller according to the current state of the order. Like, if the state of the order is unconfirmed then redirect the user to details page and then change the state to pending. If some client would need to do some validation, then register an intermediate state between unconfirmed and pending Please suggest.

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