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• Parallel Port Problem in 12.04

  - by Frank Oberle

  I have a “dumb” printer attached to a parallel port in my machine which works fine under the “other” resident operating system (from Redmond) on the same machine. I recently added Ubuntu 12.04 as a dual boot on the machine, but Ubuntu doesn't seem to recognize the parallel port at all. All I need to set up a printer is a really plain-vanilla fixed pitch text-only generic driver, which is present, but no parallel ports show up. (The other printers, all on USB ports, seem to work just fine). Following what appeared to me to be the most reasonable of the many conflicting pieces of advice on the web, here's what I did: I added the following lines to /etc/modules parport_pc ppdev parport Then, after rebooting, I checked to see that the lines were still present, and they were. I ran dmesg | grep par and got the following references in the output that seemed like they might have to do with the parallel port: [ 14.169511] parport_pc 0000:03:07.0: PCI INT A -> GSI 21 (level, low) -> IRQ 21 [ 14.169516] PCI parallel port detected: 9710:9805, I/O at 0xce00(0xcd00), IRQ 21 [ 14.169577] parport0: PC-style at 0xce00 (0xcd00), irq 21, using FIFO [PCSPP,TRISTATE,COMPAT,ECP] [ 14.354254] lp0: using parport0 (interrupt-driven). [ 14.571358] ppdev: user-space parallel port driver [ 16.588304] type=1400 audit(1347226670.386:5): apparmor="STATUS" operation="profile_load" name="/usr/lib/cups/backend/cups-pdf" pid=964 comm="apparmor_parser" [ 16.588756] type=1400 audit(1347226670.386:6): apparmor="STATUS" operation="profile_load" name="/usr/sbin/cupsd" pid=964 comm="apparmor_parser" [ 16.673679] type=1400 audit(1347226670.470:7): apparmor="STATUS" operation="profile_load" name="/usr/lib/lightdm/lightdm/lightdm-guest-session-wrapper" pid=1010 comm="apparmor_parser" [ 16.675252] type=1400 audit(1347226670.470:8): apparmor="STATUS" operation="profile_load" name="/usr/lib/telepathy/mission-control-5" pid=1014 comm="apparmor_parser" [ 16.675716] type=1400 audit(1347226670.470:9): apparmor="STATUS" operation="profile_load" name="/usr/lib/telepathy/telepathy-*" pid=1014 comm="apparmor_parser" [ 16.676636] type=1400 audit(1347226670.474:10): apparmor="STATUS" operation="profile_replace" name="/usr/lib/cups/backend/cups-pdf" pid=1015 comm="apparmor_parser" [ 16.677124] type=1400 audit(1347226670.474:11): apparmor="STATUS" operation="profile_replace" name="/usr/sbin/cupsd" pid=1015 comm="apparmor_parser" [ 1545.725328] parport0: ppdev0 forgot to release port I have no idea what any of that means, but the line “parport0: ppdev0 forgot to release port ” seems unusual. I was still unable to add a printer for my old clunker, so I tried the direct approach, typing echo “Hello” > /dev/lp0 and received a Permission denied message. I then tried echo “Hello” > /dev/parport0 which didn't give me any message at all, but still didn't print anything. Running the command sudo /usr/lib/cups/backend/parallel gives the following: direct parallel:/dev/lp0 "unknown" "LPT #1" "" "" Checking the permissions for /dev/parport0, Owner, Group, and Other are all set to read and write. crw-rw---- 1 root lp 6, 0 Sep 9 16:37 /dev/lp0 crw-rw-rw- 1 root lp 99, 0 Sep 9 16:37 /dev/parport0 The output of the command lpinfo -v includes the following line: direct parallel:/dev/lp0 I've read several web postings that seem to suggest this has been a problem for several years, but the bug reports were closed because there wasn't enough information to address the issue (shades of Microsoft!). Any suggestions as to what I might be missing here?

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• MatheMagics - Guess My Age Method 1

  - by PointsToShare

  © 2011 By: Dov Trietsch. All rights reserved MatheMagic – Guess My Age – Method 1 The Mathemagician stands on the stage and asks an adult to do the following: ·         Do the next few steps on your calculator, or the calculator in your phone, or even on a piece of paper. ·         Do it silently! Don’t tell me the results until I ask for them directly ·         Compute a single digit multiple of 9 – any one of 9, 18, 27, … all the way to 81, will do. ·         Now multiply your age by 10 ·         Subtract the 9 multiple from this number. ·         Tell me the result. Notice that I don’t know which multiple of 9 you subtracted from 10 times your age. I will nonetheless immediately tell you what your age is. How do I do this? Let’s do the algebra. 10X – 9Y = 10X – 10Y + Y = 10(X – Y) + Y Now remember, you asked an adult, so his/her age is a two digit number (maybe even 3 digits), thus reducing it by the single digit multiplied by nine is still positive – the lowest is can be is 100 – 81 which yields 19. Now make two numbers out of the result. The last digit and the number before it. This number is X – Y or the age minus the single digit you selected. The last digit is this very single digit. This is always so regardless of the digit you selected. So… Add tis digit to the other number and you get back the age! Q.E.D Example: I am 76 years old and here is what happens when I do the steps 76 x 10 = 760 760 – 18 = 742 made of 74 and 2. My age is 74 + 2 760 – 81 = 679 made of 67 and 9. My age is 67 + 9 A note to the socially aware mathemagician – it is safer to do it with a man. The chances of a veracious answer are much, much higher! The trick may be accomplished on any 2 or 3 digit number, not just one’s age, but if you want to know your date’s age, it’s a good way to elicit it. That’s All Folks PS for more Ageless “Age” mathemagics go to www.mgsltns.com/games.htm and also here: http://geekswithblogs.net/PointsToShare/archive/2011/11/15/mathemagics---guess-my-age---method-2.aspx

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• Compiling for T4

  - by Darryl Gove

  I've recently had quite a few queries about compiling for T4 based systems. So it's probably a good time to review what I consider to be the best practices. Always use the latest compiler. Being in the compiler team, this is bound to be something I'd recommend But the serious points are that (a) Every release the tools get better and better, so you are going to be much more effective using the latest release (b) Every release we improve the generated code, so you will see things get better (c) Old releases cannot know about new hardware. Always use optimisation. You should use at least -O to get some amount of optimisation. -xO4 is typically even better as this will add within-file inlining. Always generate debug information, using -g. This allows the tools to attribute information to lines of source. This is particularly important when profiling an application. The default target of -xtarget=generic is often sufficient. This setting is designed to produce a binary that runs well across all supported platforms. If the binary is going to be deployed on only a subset of architectures, then it is possible to produce a binary that only uses the instructions supported on these architectures, which may lead to some performance gains. I've previously discussed which chips support which architectures, and I'd recommend that you take a look at the chart that goes with the discussion. Crossfile optimisation (-xipo) can be very useful - particularly when the hot source code is distributed across multiple source files. If you're allowed to have something as geeky as favourite compiler optimisations, then this is mine! Profile feedback (-xprofile=[collect: | use:]) will help the compiler make the best code layout decisions, and is particularly effective with crossfile optimisations. But what makes this optimisation really useful is that codes that are dominated by branch instructions don't typically improve much with "traditional" compiler optimisation, but often do respond well to being built with profile feedback. The macro flag -fast aims to provide a one-stop "give me a fast application" flag. This usually gives a best performing binary, but with a few caveats. It assumes the build platform is also the deployment platform, it enables floating point optimisations, and it makes some relatively weak assumptions about pointer aliasing. It's worth investigating. SPARC64 processor, T3, and T4 implement floating point multiply accumulate instructions. These can substantially improve floating point performance. To generate them the compiler needs the flag -fma=fused and also needs an architecture that supports the instruction (at least -xarch=sparcfmaf). The most critical advise is that anyone doing performance work should profile their application. I cannot overstate how important it is to look at where the time is going in order to determine what can be done to improve it. I also presented at Oracle OpenWorld on this topic, so it might be helpful to review those slides.

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• GAME MAKER Problem with sprites! Can't see the sprite after mouse action

  - by user46882

  I have got a problem in Game Maker Pro: http://www.directupload.net/file/d/3646/egdpdu6u_gif.htm At the start we see a white square moving. If I press a key the square stop to move and the background changes to white. If the background changes to white a new animation/sprite should play on the same position where the white square was. BUT IT DOESNT! (Actually it is still there! It just does not move and this is fine) The animation is basically a sprite animation with some outlines of the square. If I press a key again, the background changes to white and we see the animation of the sprite.. but we do not see the animation of the sprites when it does not move. And this is strange!! I want to have the animation of the square when it doesn't move. But I don't get it.. by the way.. the .gif is a old version. I allready fixed the problem with the moving animation.. but I am still not able to play the animation if the square does not fly. The color of the animation is allready set to green or something! for better contrast. But still.. can't see it. Here is the code: obj.weisse.kugel.stepevent = the white square with the movements and sprite animations etc. if (global.kweiss == 1 ) { // vspeed = 8; //visible = true // sprite_index=spr_weisse_kugel; image_speed = 0; image_index = 0; } else if (global.kweiss == 0) { sprite_index=spr_animation_fade_out; image_speed =0.2; image_index=image_number-1 vspeed = 0; //visible = false // } then I have 1 create event for all the global.variables obj.global_var globalvar kweiss; kweiss = 1; globalvar kschwarz; kschwarz = 0; and then I have 1 controll stepevent in a new obj: if device_mouse_check_button_pressed (0, mb_left) { if background_color = c_black { background_color = c_white } else { background_color = c_black } // change of the square to white if (global.kweiss = 0) { global.kweiss = 1; } else { global.kweiss = 0; } if (global.kschwarz = 0) // change the square to black (other bullets.. we do not need this at the moment!) { global.kschwarz = 1; } else { global.kschwarz = 0; } Many thanks in advance

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• How do I take responsibility for my code when colleague makes unnecessary improvements without notice?

  - by Jesslyn

  One of my teammates is a jack of all trades in our IT shop and I respect his insight. However, sometimes he reviews my code (he's second in command to our team leader, so that's expected) without a heads up. So sometimes he reviews my changes before they complete the end goal and makes changes right away... and has even broken my work once. Other times, he has made unnecessary improvements to some of my code that is 3+ months old. This annoys me for a few reasons: I am not always given a chance to fix my mistakes He has not taken the time to ask me what I was trying to accomplish when he is confused, which could affect his testing or changes I don't always think his code is readable Deadlines are not an issue and his current workload doesn't require any work in my projects other than reviewing my code changes. Anyways, I have told him in the past to please keep me posted if he sees something in my work that he wants to change so that I could take ownership of my code (maybe I should have said "shortcomings") and he's not been responsive. I fear that I may come off as aggressive when I ask him to explain his changes to me. He's just a quiet person who keeps to himself, but his actions continue. I don't want to banish him from making code changes (not like I could), because we are a team--but I want to do my part to help our team. Added clarifications: We share 1 development branch. I do not wait until all my changes complete a single task because I risk losing some significant work--so I make sure my changes build and do not break anything. My concern is that my teammate doesn't explain the reason or purpose behind his changes. I don't think he should need my blessing, but if we disagree on an approach I thought it would be best to discuss the pros and cons and make a decision once we both understand what is going on. I have not discussed this with our team lead yet as I would prefer to resolve personal disagreements without getting management involved unless it is necessary. Since my concern seemed more of personal issue than a threat to our work, I chose to not bother the team lead. I am working on code review process ideas--to help promote the benefits of more organized code reviews without making it all about my pet peeves.

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• Common SOA Problems by C2B2

  - by JuergenKress

  SOA stands for Service Oriented Architecture and has only really come together as a concrete approach in the last 15 years or so, although the concepts involved have been around for longer. Oracle SOA Suite is based around the Service Component Architecture (SCA) devised by the Open SOA collaboration of companies including Oracle and IBM. SCA, as used in SOA suite, is designed as a way to crystallise the concepts of SOA into a standard which ensures that SOA principles like the separation of application and business logic are maintained. Orchestration or Integration? A common thing to see with many people who are beginning to either build a new SOA based infrastructure, or move an old system to be service oriented, is confusion in the purpose of SOA technologies like BPEL and enterprise service buses. For a lot of problems, orchestration tools like BPEL or integration tools like an ESB will both do the job and achieve the right objectives; however it’s important to remember that, although a hammer can be used to drive a screw into wood, that doesn’t mean it’s the best way to do it. Service Integration is the act of connecting components together at a low level, which usually results in a single external endpoint for you to expose to your customers or other teams within your organisation – a simple product ordering system, for example, might integrate a stock checking service and a payment processing service. Process Orchestration, however, is generally a higher level approach whereby the (often externally exposed) service endpoints are brought together to track an end-to-end business process. This might include the earlier example of a product ordering service and couple it with a business rules service and human task to handle edge-cases. A good (but not exhaustive) rule-of-thumb is that integrations performed by an ESB will usually be real-time, whereas process orchestration in a SOA composite might comprise processes which take a certain amount of time to complete, or have to wait pending manual intervention. BPEL vs BPMN For some, with pre-existing SOA or business process projects, this decision is effectively already made. For those embarking on new projects it’s certainly an important consideration for those using Oracle SOA software since, due to the components included in SOA Suite and BPM Suite, the choice of which to buy is determined by what they offer. Oracle SOA suite has no BPMN engine, whereas BPM suite has both a BPMN and a BPEL engine. SOA suite has the ESB component “Mediator”, whereas BPM suite has none. Decisions must be made, therefore, on whether just one or both process modelling languages are to be used. The wrong decision could be costly further down the line. Design for performance: Read the complete article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Technorati Tags: C2B2,SOA best practice,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

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• Should EICAR be updated to test the revision of Antivirus system?

  - by makerofthings7

  I'm posting this here since programmers write viruses, and AV software. They also have the best knowledge of heuristics and how AV systems work (cloaking etc). The EICAR test file was used to functionally test an antivirus system. As it stands today almost every AV system will flag EICAR as being a "test" virus. For more information on this historic test virus please click here. Currently the EICAR test file is only good for testing the presence of an AV solution, but it doesn't check for engine file or DAT file up-to-dateness. In other words, why do a functional test of a system that could have definition files that are more than 10 years old. With the increase of zero day threats it doesn't make much sense to functionally test your system using EICAR. That being said, I think EICAR needs to be updated/modified to be effective test that works in conjunction with an AV management solution. This question is about real world testing, without using live viruses... which is the intent of the original EICAR. That being said I'm proposing a new EICAR file format with the appendage of an XML blob that will conditionally cause the Antivirus engine to respond. X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-EXTENDED-ANTIVIRUS-TEST-FILE!$H+H* <?xml version="1.0"?> <engine-valid-from>2010-1-1Z</engine-valid-from> <signature-valid-from>2010-1-1Z</signature-valid-from> <authkey>MyTestKeyHere</authkey> In this sample, the antivirus engine would only alert on the EICAR file if both the signature or engine file is equal to or newer than the valid-from date. Also there is a passcode that will protect the usage of EICAR to the system administrator. If you have a backgound in "Test Driven Design" TDD for software you may get that all I'm doing is applying the principals of TDD to my infrastructure. Based on your experience and contacts how can I make this idea happen?

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• What shall I include in a 10 week web technologies course?

  - by Iain

  In September I will be teaching a university module on web technologies. This session will be available to 1st year (freshman) students who don't necessarily have any programming knowledge or know how the web works. In the 2nd semester I will be teaching Flash, which is my specialism, so I know exactly what I am going to teach, but in the 1st semester I will be teaching them web standards technologies - HTML, CSS, JS, jQuery, PHP and MySQL. Where I need advice is how to proportion the emphasis for each part, and which parts of each technology to cover. Another real issue I'm struggling with is how much of the bad old ways should I teach them? Do they need to know about bold as well as strong, etc. UPDATE: based, on your feedback I will only be teaching the latest version of everything - CSS3, HTML5 etc. I'm not sure exactly how long the semester will be but I'm guessing about 10-12 weeks. Each session is a 2 hour lab. Obviously there's only so much I can cover in that time and it will be up to the students to go a research this stuff properly on W3 schools etc. My ideas so far were: Lesson 0 - Course intro and overview of the current tech landscape. What is out there, what will we be learning, what won't we. What is a web server, URL etc. Looking at different example websites and discussing how they work. Lesson 1 - HTML basics (head, body, title, img, table, a, lists, h1, strong etc) Lesson 2 - CSS for styling and layout - fonts, webfonts, float etc Lesson 3 - Intro to programming JS (variables, loops, conditionals, functions) Lesson 4 - more JS programming fundamentals, DOM manipulation Lesson 5 - jQuery - making things fly about and look cool Lesson 6 - XML and Ajax Lesson 7 - PHP basics - syntax, server-side principles Lesson 8 - PHP and MySQL - forms, logins, saving user info Lesson 9 - don't know Lesson 10 - don't know Please let me know if you think this is the right order, what have I missed, how to use any spare sessions etc. Thanks :) UPDATE BASED ON RESPONSES: Thanks for all your responses - some great stuff. To be absolutely clear, this is not a computer science course, it is a practical module on a creative technology course. The emphasis definitely has to be on making cool things work rather than understanding how the backbone of the internet works. That can come later, if the students are interested. At the end of the module I would like the students to be able to produce a web page or pages that does something cool, using some or all of the technologies I cover. Many of these topics are of course far beyond the scope of a 2 hour session, however I do not have the option of reducing the syllabus, I will just have to explain what the technology does and encourage the student to research it in their own time.

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• Access denied 403 errors after migrating my site

  - by AgA

  I've recently migrated my Joomla site from one shared hosting to another with Hostgator. GWT notified me about many 403 access denied pages. I've checked with Firebug too, and even though browser is displaying full page correctly but http return is 403. I've checked the home page but it's correctly returing 200 response. The same is shown by Fetch as Google in GWT(pasted this in the bottom). The site is 3 years old and I regularly do such migrations. I've copied the files and database "AS IS". I've even cleared all the caches but no luck. There is only one change: previously the site was primary domain but now it's add-on one. What could be the issue? This is how Googlebot fetched the page. Fetch as Google URL: http://MYSITE.COM/-----------------REMOVED.html Date: Thursday, June 20, 2013 at 10:32:14 PM PDT Googlebot Type: Web Download Time (in milliseconds): 3899 HTTP/1.1 403 Forbidden Date: Fri, 21 Jun 2013 05:32:15 GMT Server: Apache P3P: CP="NOI ADM DEV PSAi COM NAV OUR OTRo STP IND DEM" Expires: Mon, 1 Jan 2001 00:00:00 GMT Cache-Control: post-check=0, pre-check=0 Pragma: no-cache Set-Cookie: 0e4f6b53991c80cf39d57a6db58bb58d=ee2d880e8db0f1fc03c5612ea5a77004; path=/ Last-Modified: Fri, 21 Jun 2013 05:32:19 GMT Keep-Alive: timeout=5, max=75 Connection: Keep-Alive Transfer-Encoding: chunked Content-Type: text/html; charset=utf-8 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-gb" lang="en-gb" > <head> <base href="http://www.mysite.com/-----------------rajiv-yuva-shakthi-programme-finance-planning.html" /> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <meta name="robots" content="index, follow" /> <meta name="keywords" content="" /> <<<<<<TRIMMED>>>>>>>>>>>>>>

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• Best way to implement a simple bullet trajectory

  - by AirieFenix

  I searched and searched and although it's a fair simple question, I don't find the proper answer but general ideas (which I already have). I have a top-down game and I want to implement a gun which shoots bullets that follow a simple path (no physics nor change of trajectory, just go from A to B thing). a: vector of the position of the gun/player. b: vector of the mouse position (cross-hair). w: the vector of the bullet's trajectory. So, w=b-a. And the position of the bullet = [x=x0+speed*time*normalized w.x , y=y0+speed*time * normalized w.y]. I have the constructor: public Shot(int shipX, int shipY, int mouseX, int mouseY) { //I get mouse with Gdx.input.getX()/getY() ... this.shotTime = TimeUtils.millis(); this.posX = shipX; this.posY = shipY; //I used aVector = aVector.nor() here before but for some reason didn't work float tmp = (float) (Math.pow(mouseX-shipX, 2) + Math.pow(mouseY-shipY, 2)); tmp = (float) Math.sqrt(Math.abs(tmp)); this.vecX = (mouseX-shipX)/tmp; this.vecY = (mouseY-shipY)/tmp; } And here I update the position and draw the shot: public void drawShot(SpriteBatch batch) { this.lifeTime = TimeUtils.millis() - this.shotTime; //position = positionBefore + v*t this.posX = this.posX + this.vecX*this.lifeTime*speed*Gdx.graphics.getDeltaTime(); this.posY = this.posY + this.vecY*this.lifeTime*speed*Gdx.graphics.getDeltaTime(); ... } Now, the behavior of the bullet seems very awkward, not going exactly where my mouse is (it's like the mouse is 30px off) and with a random speed. I know I probably need to open the old algebra book from college but I'd like somebody says if I'm in the right direction (or points me to it); if it's a calculation problem, a code problem or both. Also, is it possible that Gdx.input.getX() gives me non-precise position? Because when I draw the cross-hair it also draws off the cursor position. Sorry for the long post and sorry if it's a very basic question. Thanks!

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• Software Tuned to Humanity

  - by Phil Factor

  I learned a great deal from a cynical old programmer who once told me that the ideal length of time for a compiler to do its work was the same time it took to roll a cigarette. For development work, this is oh so true. After intently looking at the editing window for an hour or so, it was a relief to look up, stretch, focus the eyes on something else, and roll the possibly-metaphorical cigarette. This was software tuned to humanity. Likewise, a user’s perception of the “ideal” time that an application will take to move from frame to frame, to retrieve information, or to process their input has remained remarkably static for about thirty years, at around 200 ms. Anything else appears, and always has, to be either fast or slow. This could explain why commercial applications, unlike games, simulations and communications, aren’t noticeably faster now than they were when I started programming in the Seventies. Sure, they do a great deal more, but the SLAs that I negotiated in the 1980s for application performance are very similar to what they are nowadays. To prove to myself that this wasn’t just some rose-tinted misperception on my part, I cranked up a Z80-based Jonos CP/M machine (1985) in the roof-space. Within 20 seconds from cold, it had loaded Wordstar and I was ready to write. OK, I got it wrong: some things were faster 30 years ago. Sure, I’d now have had all sorts of animations, wizzy graphics, and other comforting features, but it seems a pity that we have used all that extra CPU and memory to increase the scope of what we develop, and the graphical prettiness, but not to speed the processes needed to complete a business procedure. Never mind the weight, the response time’s great! To achieve 200 ms response times on a Z80, or similar, performance considerations influenced everything one did as a developer. If it meant writing an entire application in assembly code, applying every smart algorithm, and shortcut imaginable to get the application to perform to spec, then so be it. As a result, I’m a dyed-in-the-wool performance freak and find it difficult to change my habits. Conversely, many developers now seem to feel quite differently. While all will acknowledge that performance is important, it’s no longer the virtue is once was, and other factors such as user-experience now take precedence. Am I wrong? If not, then perhaps we need a new school of development technique to rival Agile, dedicated once again to producing applications that smoke the rear wheels rather than pootle elegantly to the shops; that forgo skeuomorphism, cute animation, or architectural elegance in favor of the smell of hot rubber. I struggle to name an application I use that is truly notable for its blistering performance, and would dearly love one to do my everyday work – just as long as it doesn’t go faster than my brain.

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• My father wants to learn PHP-MySQL to port his application. What I should do to help?

  - by adijiwa

  My father is a doctor/physician. About 15 years ago he started writing an application to handle his patient's medical records in his clinic at home. The app has the ability to input patient's medical records (obviously), search patients by some criteria, manage medicine stocks, output receipt to printer, and some more CRUDs. He wrote it in dBase III+. A few years later he migrated to FoxPro 2.6 for DOS and finally in a few more years he rewrote his app in Visual FoxPro 9. And now (actually two years ago) he wants to rewrite it in PHP, but he don't know how. The Visual FoxPro version of this app is still running and has no serious problem except sometimes it performs slowly. Usually there are 1-5 concurrent users. The binary and database files are shared via windows share. He did all the coding as a hobby and for free (it is for his own clinic after all). He also use this app in two other offices he managed. Some reasons of why he wants to rewrite in PHP-MySQL: He wants to learn Easier to deploy (?) Easier client setup, need only a browser What should I do to help my father? How should he start? I explored some options: I let my father learn PHP and MySQL (and HTML (and JavaScript?)) from scratch. I create/bundle framework. I'm thinking on bundling CodeIgniter and a web UI framework (any suggestion?) especially to reduce effort on writing presentation codes. What do you think? tl;dr My father (a doctor) wants to rewrite his Visual FoxPro app in PHP-MySQL. He knows very little of PHP and MySQL but he wants to learn. What should I do to help? How should he start? Some facts: My father is 50 years old. His first encounter with a PC is in early 1980s. It was IBM PC with Intel 8088. He knows BASIC. He taught me how to use DOS and how to program with BASIC. The other language he knows fairly well is dBase/FoxPro. I got my bachelor CS degree last year. I know the internals of my father's app because sometime he wants me to help him writing his app. Sorry for my english.

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• I need help installing Ubuntu 11.10 to multi-drive system

  - by CookyMonzta

  I have a machine with 3 hard drives; the primary, which is 750GB (drive 0), and 2 others, each of which is 640GB (drives 1 and 2). On the last screen before the actual installation begins, this is how my hard drive configuration looks: /dev/sda [DISK0, 750GB] /dev/sda1 ntfs 104MB [Win7 System Reserved] /dev/sda2 ntfs 499,997MB [Windows 7 Pro] free space 250,052MB [This space intended for Windows 8] /dev/sdb [DISK1, 640GB] /dev/sdb1 ntfs 400,085MB [Windows XP Pro] free space 240,049MB [This space intended for Ubuntu] /dev/sdc [DISK2, 640GB] [This drive intended for various backups] free space 160,033MB /dev/sdc5 ntfs 480,101MB [Acronis Secure Zone] As you can see, I have 3 drives, all SATA. I have Win7 on my first drive (0), WinXP on my second drive (1) and a secure zone for daily backups on my third drive (2). I want to put Ubuntu 11.10 Oneiric Ocelot on the drive that also has XP. I've already used 400GB for XP and I have 240GB remaining, for which, my intention was to create a 4GB swap file and use the rest for Ubuntu itself. This is what my second hard drive looked like, for my intended setup before installation: /dev/sdb /dev/sdb5 swap 4,095MB [Linux swap] /dev/sdb6 ext4 235,951MB [Ubuntu 11.10] Needless to say, this is only the second time I have attempted to install Linux. I managed to get 7.10 Gutsy Gibbon working on an old machine. I have two problems with this installation: Ubuntu asks for a location to install the boot loader (i.e., "Device for Boot Loader Installation"). I already have a boot loader; namely, Acronis OS Selector (from Acronis Disk Director 11). So I decided to put the Ubuntu boot loader in /dev/sdb6 (where I intend to install Ubuntu), to keep it from interfering with my Acronis OS Selector. Once I hit "Install now", I ended up with the following error: "No root file system is defined. Please correct this from the partitioning menu." What am I missing? Did I attempt to put the boot loader in the wrong place? I assume I did, because as I am writing this entry, I am looking at LinuxIdentity.com's Ubuntu 11.04 Natty Narwhal magazine, and I see a screenshot (Figure 7 on Page 13) that implies that the boot loader can be installed anywhere, including the first hard drive (in the MBR, which would obviously force me to reinstall the Acronis OS Selector) or even on a floppy. But why do I get an undefined root file system error? I thought /dev/sdb6 was the root file. Obviously I'm missing something in the installation procedure. Should I try installing it in Windows using the WUBI Installer? I assume that, if I attempt to install Ubuntu from WinXP (on the second drive), it will automatically install Ubuntu on the empty partition alongside XP. But will I have the option of creating a swap partition? And what if the WUBI Installer searches all of my drives and decides to install Ubuntu on my first drive's empty partition (which I have left empty for Win8 upon its release)?

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• "static" as a semantic clue about statelessness?

  - by leoger

  this might be a little philosophical but I hope someone can help me find a good way to think about this. I've recently undertaken a refactoring of a medium sized project in Java to go back and add unit tests. When I realized what a pain it was to mock singletons and statics, I finally "got" what I've been reading about them all this time. (I'm one of those people that needs to learn from experience. Oh well.) So, now that I'm using Spring to create the objects and wire them around, I'm getting rid of static keywords left and right. (If I could potentially want to mock it, it's not really static in the same sense that Math.abs() is, right?) The thing is, I had gotten into the habit of using static to denote that a method didn't rely on any object state. For example: //Before import com.thirdparty.ThirdPartyLibrary.Thingy; public class ThirdPartyLibraryWrapper { public static Thingy newThingy(InputType input) { new Thingy.Builder().withInput(input).alwaysFrobnicate().build(); } } //called as... ThirdPartyLibraryWrapper.newThingy(input); //After public class ThirdPartyFactory { public Thingy newThingy(InputType input) { new Thingy.Builder().withInput(input).alwaysFrobnicate().build(); } } //called as... thirdPartyFactoryInstance.newThingy(input); So, here's where it gets touchy-feely. I liked the old way because the capital letter told me that, just like Math.sin(x), ThirdPartyLibraryWrapper.newThingy(x) did the same thing the same way every time. There's no object state to change how the object does what I'm asking it to do. Here are some possible answers I'm considering. Nobody else feels this way so there's something wrong with me. Maybe I just haven't really internalized the OO way of doing things! Maybe I'm writing in Java but thinking in FORTRAN or somesuch. (Which would be impressive since I've never written FORTRAN.) Maybe I'm using staticness as a sort of proxy for immutability for the purposes of reasoning about code. That being said, what clues should I have in my code for someone coming along to maintain it to know what's stateful and what's not? Perhaps this should just come for free if I choose good object metaphors? e.g. thingyWrapper doesn't sound like it has state indepdent of the wrapped Thingy which may itself be mutable. Similarly, a thingyFactory sounds like it should be immutable but could have different strategies that are chosen among at creation. I hope I've been clear and thanks in advance for your advice!

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• Small script to look for Project Replication actions that have failed

  - by Trond Strømme

  Today when looking at a couple of projects on a ZFS 7320 Storage Appliance I noticed on one project that one of its replication actions had failed, as I hadn't checked the Recent Alerts log yet I was not aware of this. I decided to write a small script to check if there were others that had failed. Nothing fancy, just a loop through all projects, look at the project's replication child and compare the values of the last_sync and last_try properties and print the result if they're not equal. (There are probably more sensible ways of doing this, but at least it involves me getting the chance to put on my headphones and doing just a little bit of coding.) script // this script will locate failed project level replication // it will look at the sync times for 'last_sync' and 'last_try' // and compare these, if they deviate you should investigate. // NOTE! this code is offered 'as is' Run at your own risk, // it will probably work as intended, but in now way can I // (or Oracle) be held responsible if your server starts behaving // like a three year old kid in a candy store.. (not that mine do, // they are very well behaved boys...) run('configuration'); run('storage'); printf('Host: %s, pool: %s\n', get('owner'),get('pool')); run('cd /'); run('shares'); proj=list(); printf("total projects: %d\n",proj.length +'\n'); // just for project level replication for(i=0;i<proj.length;i++){ run('select '+proj[i]); run('replication'); //get all replication actions preps = list(); for(j=0;j<preps.length;j++){ run('select ' + preps[j]); last_sync = get('last_sync'); last_try = get('last_try'); // printf("target %s\n", get('target')); //why the flip does this not get the proper name? if(!( last_sync.valueOf() === last_try.valueOf())){ printf("sync has failed for %s %s\n", proj[i], get('target')); }else{ // printf("OK %s %s\n", proj[i], get('target')); } run('done'); //done with the replica action } run('done'); run('done'); } printf("finished\n"); For a more on how to run the script, or testing it please look at my previous post. Sample output: Host: elb1sn01, pool: exalogic total projects: 45 sync has failed for ACSExalogicSystem cb3a24fe-ad60-c90f-d15d-adaafd595639 finished

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• Ask the Readers: Which Browser is a Must-Have for You on Linux?

  - by Asian Angel

  Linux systems all come with their own particular set of default browsers, but those browsers may not be the ones you want or need. This week we would like to know which browser (or browsers) are considered “must-have” on your Linux systems. As a general rule many Linux distributions have Firefox and/or Konqueror as one of the default installation browsers. During this past year the open source browser Chromium has also been gaining a lot of traction as a default install for systems. For most people these browsers are the ones that they like best or feel work well enough to not make any changes. But there are other people who want more than what is available with a default system install. They may favor a particular browser for its’ extensibility or speed…others prefer a particular browser for its’ features or minimalist UI. Whatever your preferences may be, there is a browser out there to fit your style. Some people may even prefer to run only bleeding edge nightly releases or add them in with their current browsers. The important part is that you have choices when it comes to your Linux system. What we would like to know this week is which browser or browsers you make sure are always installed on your Linux systems. Does the Linux system you use already have your favorite browser installed as part of the default set? Maybe you are content with using the default set of browsers that come with the system. Or perhaps you prefer to rework the entire browser setup on your system by removing the defaults and adding your favorites. Let us know which browsers you consider “must have” and why in the comments! Note: You can make up to two selections on today’s poll since most people will likely have more than one browser that they make certain is always installed. How-To Geek Polls require Javascript. Please Click Here to View the Poll. Latest Features How-To Geek ETC How To Boot 10 Different Live CDs From 1 USB Flash Drive The 20 Best How-To Geek Linux Articles of 2010 The 50 Best How-To Geek Windows Articles of 2010 The 20 Best How-To Geek Explainer Topics for 2010 How to Disable Caps Lock Key in Windows 7 or Vista How to Use the Avira Rescue CD to Clean Your Infected PC BotSync Enables Secure FTP File Synchronization on Android Devices Enjoy Beautiful City Views with the Cityscape Theme for Windows 7 Luigi Installs Any OS on Google’s Cr-48 Notebook DIY iPad Stylus Offers Pen-Based Interaction on the Cheap Serene Blue Ubuntu Wallpaper for Your Desktop Enjoy Old School Style Video Game Fun with Chicken Invaders

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• How Do I Do Alpha Transparency Properly In XNA 4.0?

  - by Soshimo

  Okay, I've read several articles, tutorials, and questions regarding this. Most point to the same technique which doesn't solve my problem. I need the ability to create semi-transparent sprites (texture2D's really) and have them overlay another sprite. I can achieve that somewhat with the code samples I've found but I'm not satisfied with the results and I know there is a way to do this. In mobile programming (BREW) we did it old school and actually checked each pixel for transparency before rendering. In this case it seems to render the sprite below it blended with the alpha above it. This may be an artifact of how I'm rendering the texture but, as I said before, all examples point to this one technique. Before I go any further I'll go ahead and paste my example code. public void Draw(SpriteBatch batch, Camera camera, float alpha) { int tileMapWidth = Width; int tileMapHeight = Height; batch.Begin(SpriteSortMode.Texture, BlendState.AlphaBlend, SamplerState.PointWrap, DepthStencilState.Default, RasterizerState.CullNone, null, camera.TransformMatrix); for (int x = 0; x < tileMapWidth; x++) { for (int y = 0; y < tileMapHeight; y++) { int tileIndex = _map[y, x]; if (tileIndex != -1) { Texture2D texture = _tileTextures[tileIndex]; batch.Draw( texture, new Rectangle( (x * Engine.TileWidth), (y * Engine.TileHeight), Engine.TileWidth, Engine.TileHeight), new Color(new Vector4(1f, 1f, 1f, alpha ))); } } } batch.End(); } As you can see, in this code I'm using the overloaded SpriteBatch.Begin method which takes, among other things, a blend state. I'm almost positive that's my problem. I don't want to BLEND the sprites, I want them to be transparent when alpha is 0. In this example I can set alpha to 0 but it still renders both tiles, with the lower z ordered sprite showing through, discolored because of the blending. This is not a desired effect, I want the higher z-ordered sprite to fade out and not effect the color beneath it in such a manner. I might be way off here as I'm fairly new to XNA development so feel free to steer me in the correct direction in the event I'm going down the wrong rabbit hole. TIA

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• Got Samba, Got PyNeighbourhood but still no connection. What else do I need?

  - by Frank A

  I am sure I had already hit post before but then could only find it by backing through browser. Was it deleted? is the question too dumb, sorry that I do not know the right jargon just trying to get answers to my problem anyway have reworded stuff a bit This seems to be a number one requirement for lots of people and 2 months on from setting up my Ubuntu pc, I am still unable to get a lasting connection in either direction. Adding a windows pc to a network is so easy... just a few clicks and get on with using it all. Using all command approaches and modifying configuration files is hardly user friendly. Googling brings up thousands of solutions but mostly they are too techy or assume the user is fully aware of how to use Linux. I do realise that their must be a lot of flavours for connecting to networks. So far I have installed Samba and fiddled with its config file. The day I did all that it worked from XP to Ubuntu. When I came back two days later to transfer my data over it would not connect. Although the the share does show up in Windows (XP) My Network Places. Today I installed PyNeighbourhood and this shows the Ubuntu box and all of the shares I had created at some point on Ubuntu and it even shows this under the XP workgroup name. But instructions on setting the connection up seem to relate to an earlier version and nothing seems to work there either. (I unshared most of those test folders but they still show up her but that is another question. When I click on mount- I can only click on one on the Ubuntu machine, there is one with no name so I assume this to be my attempt to add one XP Shared drive using ipaddress, I get errors. (gksu:9767): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (gksu:9767): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (gksu:9767): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (gksu:9767): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", mount error(6): No such device or address Refer to the mount.cifs(8) manual page (e.g. man mount.cifs) OK tried to find the manual referred to... only an old comment that manual would be produced for future versions. I saw in another thread that Winbind is needed as well or at least I assume as well? Totally lost again? Please help, what else needs to be installed to connect to win pcs on the network.

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• Career advice: stay with PHP or start a new career in something else ( .Net?)

  - by Christian P

  I'm planning on moving to NY in 6-12 months tops, so I'm forced to find a new job. When I'm planing to start my life in another city it's also probably a good time to think about career changes. I've found a lot of different opinions about PHP vs .Net vs Java and this is not topic here. I don't want to start a new fight about which language is better. Knowing programming language is not the most important thing for being a software developer. To be a really good developer you need to know OOP, design patterns, testing... and language is just a tool to make things happen. So back to my question. I have mixed experience in IT - 1 year as an IT support guy (Windows administration and support), around 2 years of experience in embedded programming (VB.Net 2005) and for the last 2 years I'm working with PHP/MySQL. I have worked with Magento web shop, assisted in some projects in Symfony, modified few Drupal sites. My main concerns are following: Do I continue to improve my skills in PHP e.g. to start learning some major PHP framework like Zend, Symfony maybe get some PHP certification. Or do I start learning .NET or Java. I'm more familiar to .NET so I'll probably choose it if choice falls between .NET and Java ( or you could convince me to choose Java :). Career-wise, I don't know what is the best choice. Learning new framework and language is more time consuming then improving my existing skills in PHP. But with .NET you have a lot of possibilities (Windows 7 Phone development, Silverlight, WPF) and possibly bigger chances to find better jobs. PHP jobs are less payed then .NET, at least, according to my researches (correct me if I'm wrong). But if I start now with .NET I'm just a beginner and my salary will be low. I need at least 2+ years of experience in some language to even try to find some job that is paying higher than $50-60k in NY. My main goal in next 2-3 years is to try to find a job in a $60-80k category. Don't get me wrong, I'm not just chasing money, but money is an important factor when you're trying to start a family. I'm 27 years old and I feel that there isn't a lot of room for wrong decisions regarding my career, so any advice will be very welcome. Update Thank you all for spending time to help me with my problem. All of the answers and comments have been very helpful. I have decided to stick with PHP but also to learn C# and Silverlight 4. We'll see where the life will take me.

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• RTS Game Style Application [closed]

  - by Daniel Wynand van Wyk

  My question may seem somewhat odd, but I hope that my specifications will clarify EXACTLY what it is that I am after. I need some help choosing the right tooling for a particular endeavour. My background is in desktop application development and large back-end systems. I have worked primarily on the Microsoft stack using C# and the .Net framework. My goal is to develop a 2D, RTS style, interactive office simulation. The simulation will model various office spaces, office equipment, employees and their interactions with one another. The idea is to abstract the concept of an office completely. Under the hood the application will do many things that are nothing like a game. This includes P2P networking, VPN tunnelling, streaming video, instant messaging, document collaboration, remote screen sharing, file-sharing, virus scanning, VOIP, document scanning, faxing, emailing, distributed computing, content management and much more! A somewhat similar thing has been attempted by IBM, where they created a virtual office in second life. If their attempt was a game, the game-play would be notably horrible, to say the least! The users/players will drive and control my application through the various objects modelled in the simulation. A single application capable of performing all of these various tasks would be a nightmare to navigate for even the most expert user. Using the concept of a game, I can easily separate functionality by assigning them to objects that relate 1-1 with their real world counter-parts. This can greatly simplify computing for novice users, with many added benefits in terms of visibility, transparency of process and centralized configuration. My hope is to make complex computing tasks accessible to all kinds of users and to greatly reduce the cognitive load associated with using the many different utilities and applications inside office settings. The complexity is therefore limited to the complexity of the space in which you find yourself. I want the application to target as many platforms as possible and run on computers that have no accelerated graphics capabilities. The simulation won't contain any of the fancy eye-candy you find in modern games, to the contrary, my "game" will purposefully be clean and simple. The closest thing I could imagine would be an old game like "Theme Hospital" or the first instalment of "The Sims". All the content will be pre-created and not user-generated like Second Life. New functionality will be added via a plugin system. Given my background and nature of my "game", I would like to spend most of my time writing code that does not have to do with the simulated office, as the "game" is really just a glorified application menu. I have done much reading about existing engines, frameworks and tools. I need the help of an experienced game developer who has tried and tested various products over the years who can guide me in the right direction given my very particular needs. I would appreciate any help I can get!

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• Achieving decoupling in Model classes

  - by Guven

  I am trying to test-drive (or at least write unit tests) my Model classes but I noticed that my classes end up being too coupled. Since I can't break this coupling, writing unit tests is becoming harder and harder. To be more specific: Model Classes: These are the classes that hold the data in my application. They resemble pretty much the POJO (plain old Java objects), but they also have some methods. The application is not too big so I have around 15 model classes. Coupling: Just to give an example, think of a simple case of Order Header - Order Item. The header knows the item and the item knows the header (needs some information from the header for performing certain operations). Then, let's say there is the relationship between Order Item - Item Report. The item report needs the item as well. At this point, imagine writing tests for Item Report; you need have a Order Header to carry out the tests. This is a simple case with 3 classes; things get more complicated with more classes. I can come up with decoupled classes when I design algorithms, persistence layers, UI interactions, etc... but with model classes, I can't think of a way to separate them. They currently sit as one big chunk of classes that depend on each other. Here are some workarounds that I can think of: Data Generators: I have a package that generates sample data for my model classes. For example, the OrderHeaderGenerator class creates OrderHeaders with some basic data in it. I use the OrderHeaderGenerator from my ItemReport unit-tests so that I get an instance to OrderHeader class. The problem is these generators get complicated pretty fast and then I also need to test these generators; defeating the purpose a little bit. Interfaces instead of dependencies: I can come up with interfaces to get rid of the hard dependencies. For example, the OrderItem class would depend on the IOrderHeader interface. So, in my unit tests, I can easily mock the behaviour of an OrderHeader with a FakeOrderHeader class that implements the IOrderHeader interface. The problem with this approach is the complexity that the Model classes would end up having. Would you have other ideas on how to break this coupling in the model classes? Or, how to make it easier to unit-test the model classes?

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• C# Preprocessor Directives

  - by MarkPearl

  Going back to my old c++ days at university where we had all our code littered with preprocessor directives - I thought it made the code ugly and could never understand why it was useful. Today though I found a use in my C# application. The scenario – I had made various security levels in my application and tied my XAML to the levels by set by static accessors in code. An example of my XAML code for a Combobox to be enabled would be as follows… <ComboBox IsEnabled="{x:Static security:Security.SecurityCanEditDebtor}" />   And then I would have a static method like this… public static bool SecurityCanEditDebtorPostalAddress { get { if (SecurityCanEditDebtorPostalAddress) { return true; } else { return false; } } } My only problem was that my XAML did not like the if statement – which meant that while my code worked during runtime, during design time in VS2010 it gave some horrible error like… NullReferenceException was thrown on “StatiucExtension”: Exception has been thrown by the target of an invocation… If however my C# method was changed to something like this… public static bool SecurityCanEditDebtorPostalAddress { get { return true; } }   My XAML viewer would be happy. But of course this would bypass my security… <Drum Roll> Welcome preprocessor directives… what I wanted was during my design experience to totally remove the “if” code so that my accessor would return true and not have any if statements, but when I release my project to the big open world, I want the code to have the is statement. With a bit of searching I found the relevant MSDN sample and my code now looks like this… public static bool SecurityCanEditDebtorPostalAddress { get { #if DEBUG return true; #else if (Settings.GetInstance().CurrentUser.SecurityCanEditDebtorPostalAddress) { return true; } else { return false; } #endif } }   Not the prettiest beast, but it works. Basically what is being said here is that during my debug mode compile my code with just the code between the #if … #else block, but what I can now do is if I want to universally switch everything to the “if else” statement, I just go to my project properties –> Build and change the “Debug” flag as illustrated in the picture below. Also note that you can define your own conditional compilation symbols, and if you even wanted to you could skip the whole properties page and define them in code using the #define & #undef directives. So while I don’t like the way the code works and would like to look more into AOP and compare it to this method, it works for now.

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• Running a program on boot without login, using the screen

  - by configurator

  Preface: I have a server running on an old laptop. The screen is always on with a login prompt, but because its keyboard is in pretty bad shape, I use it exclusively via ssh. The screen is in a good position, though; I want to use it to display a clock and some stats about what my server is doing. I have scripts to display all those things, but I want to always show them on the monitor screen. My question is, how do I get my script (called HUD) to run on /dev/tty1, instead of the login prompt. Hopefully, it should be possible to accept keyboard input as well as display its output, so that it can use the keyboard to show more info where needed in a future version. I'd also like tty2 etc. to remain active as login screens, in face I actually do need to login locally. For a start, I tried creating a script that I can run from ssh to start the HUD. It goes something like this: ( flock -n 9 watch --interval 0.2 --precise --color --notitle --exec /path/to/script & disown ) 9> /var/lock/hud > /dev/tty1 2> /dev/tty1 < /dev/tty1 (I had to use & disown instead of nohup because nohup recognized the tty and redirects output to nohup.out instead.) This sort-of works. However, it has a few issues: It doesn't steal the terminal's keyboard input, so you can't ctrl+c to get out of it (nor change the script to actually use the keyboard input), and if you press enter it show it and scrolls the display, never refreshing it correctly afterwards. Oddly, if I disconnect the ssh session which created it, it stops working and shows a message: exec: No such file or directory. If I reconnect to ssh, it resumes functioning properly. It feels hackish. Is there a better way to do this? How?

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• 2D Collision in Canvas - Balls Overlapping When Velocity is High

  - by kushsolitary

  I am doing a simple experiment in canvas using Javascript in which some balls will be thrown on the screen with some initial velocity and then they will bounce on colliding with each other or with the walls. I managed to do the collision with walls perfectly but now the problem is with the collision with other balls. I am using the following code for it: //Check collision between two bodies function collides(b1, b2) { //Find the distance between their mid-points var dx = b1.x - b2.x, dy = b1.y - b2.y, dist = Math.round(Math.sqrt(dx*dx + dy*dy)); //Check if it is a collision if(dist <= (b1.r + b2.r)) { //Calculate the angles var angle = Math.atan2(dy, dx), sin = Math.sin(angle), cos = Math.cos(angle); //Calculate the old velocity components var v1x = b1.vx * cos, v2x = b2.vx * cos, v1y = b1.vy * sin, v2y = b2.vy * sin; //Calculate the new velocity components var vel1x = ((b1.m - b2.m) / (b1.m + b2.m)) * v1x + (2 * b2.m / (b1.m + b2.m)) * v2x, vel2x = (2 * b1.m / (b1.m + b2.m)) * v1x + ((b2.m - b1.m) / (b2.m + b1.m)) * v2x, vel1y = v1y, vel2y = v2y; //Set the new velocities b1.vx = vel1x; b2.vx = vel2x; b1.vy = vel1y; b2.vy = vel2y; } } You can see the experiment here. The problem is, some balls overlap each other and stick together while some of them rebound perfectly. I don't know what is causing this issue. Here's my balls object if that matters: function Ball() { //Random Positions this.x = 50 + Math.random() * W; this.y = 50 + Math.random() * H; //Random radii this.r = 15 + Math.random() * 30; this.m = this.r; //Random velocity components this.vx = 1 + Math.random() * 4; this.vy = 1 + Math.random() * 4; //Random shade of grey color this.c = Math.round(Math.random() * 200); this.draw = function() { ctx.beginPath(); ctx.fillStyle = "rgb(" + this.c + ", " + this.c + ", " + this.c + ")"; ctx.arc(this.x, this.y, this.r, 0, Math.PI*2, false); ctx.fill(); ctx.closePath(); } }

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• I didn't mean to become a database developer, but now I am. Should I stop or try to get better?

  - by pretlow majette

  20 years ago I couldn't afford even a cheap POS program when I opened my first surf shop in the Virgin Islands. I bought a copy of Paradox (remember that?) in 1990 and spent months in a back room scratching out a POS application. Over many iterations, including a switch to Access (2000)/SQL Server (2003), I built a POS and backoffice solution that runs four stores with multiple cash registers, a warehouse and office. Until recently, all my stores were connected to the same LAN (in a small shopping center) and performance wasn't an issue. Now that we've opened a location in the States that's changed. Connecting to my local server via the internet has slowed that locations application to a crawl. This is partly due to the slow and crappy dsl service we have in the Virgin Islands, and partly due to my less-than-professional code and sql. With other far-away stores in the works, I need a better solution. I like my application. My staff knows it well, and I'm not inclined to take on the expense of a proper commercial solution. So where does that leave me? I should probably host my sql online to sidestep the slow dsl here. I think I can handle cleaning up my SQL querries to speed that up a bit. What about Access? My version seems so old, but I don't like the newer versions with the 'ribbon'. There are so many options... Should I be learning Visual Studio with an eye on moving completely to the web? Will my VBA skills help me at all there? I don't have the luxury of a year at the keyboard to figure it out anymore. What about dotnetnuke, sharepoint, or lightswitch? They all seem like possibilities, but even understanding their capabilities is daunting. I'm pretty deep into it, but maybe I should bail and hire a consultant or programmer. That sounds expensive tho, and there's no guarantee there either... Any advice would be greatly appreciated. Or, if anybody is interested in buying a small chain of surf shops...

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