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  • Trying to configure samba share with office server

    - by tomphelps
    Hi, i'm trying to set up fstab to automatically connect to my office shared server. I'm undoubtedly doing something silly here as the username and password and server name work fine in the first code snippet below, just not the second - any help would be appreciated! The following command works as expected... tom@tom-desktop: sudo /usr/bin/smbclient -L Server.local -Uguest Enter guest's password: Domain=[WORKGROUP] OS=[Unix] Server=[Samba 3.0.10] Sharename Type Comment --------- ---- ------- Lacie Disk Disk macosx Server Disk macosx IPC$ IPC IPC Service (Server) ADMIN$ IPC IPC Service (Server) Domain=[WORKGROUP] OS=[Unix] Server=[Samba 3.0.10] Server Comment --------- ------- ACER-9D60040D10 SERVER Server Workgroup Master --------- ------- WORKGROUP ACER-9D60040D10 But when i add the following line to /etc/fstab, i get this error: cifs_mount failed w/return code = -22 //Server.local/Server /media/maguires cifs username=guest,password=password 0 0

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  • How can I improve my Animation

    - by sharethis
    The first approaches in animation for my game relied mostly on sine and cosine functions with the time as parameter. Here is an example of a very basic jump I implemented. if(jumping) { height = sin(time); if(height < 0) jumping = false; // player landed player.position.z = height; } if(keydown(SPACE) && !jumping) { jumping = true; time = now(); // store the starting time } So my player jumped in a perfect sine function. That seems quite natural, because he slows down when he reached the top position, and in the fall he speeds up again. But patching every animation out of sine and cosine is stretched to its limits soon. So can I improve my animation and provide a more abstract layer?

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  • Writing to a structured buffer with a compute shader (D3D11)

    - by Vertexwahn
    I have some problems writing to a structured buffer. First I create a structured buffer that is filled with float values beginning from 0 to 99. Afterwards a copy the structured buffer to a CPU accessible buffer is made to print the content of the structured buffer to the console. The output is as expected (Numbers 0 to 99 appear on the console). Afterwards I use a compute shader that should change the contents of the structured buffer: RWStructuredBuffer<float> Result : register( u0 ); [numthreads(1, 1, 1)] void CS_main( uint3 GroupId : SV_GroupID ) { Result[GroupId.x] = GroupId.x * 10; } But the compute shader does not change the contents of the structured buffer. The source code can be found here (main.cpp): https://bitbucket.org/Vertexwahn/cmakedemos/src/4abb067afd5781b87a553c4c720956668adca22a/D3D11ComputeShader/src/main.cpp?at=default FillCS.hlsl: https://bitbucket.org/Vertexwahn/cmakedemos/src/4abb067afd5781b87a553c4c720956668adca22a/D3D11ComputeShader/src/FillCS.hlsl?at=default

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  • Multithreading synchronization interview question: Find n words given m threads

    - by rplusg
    I came across this question: You are given a paragraph , which contain n number of words, you are given m threads. What you need to do is , each thread should print one word and give the control to next thread, this way each thread will keep on printing one word , in case last thread come, it should invoke the first thread. Printing will repeat until all the words are printed in paragraph. Finally all threads should exit gracefully. What kind of synchronization will use? I strongly feel we cannot take any advantage of threads here but interviewer is trying to understand my synchronization skills? No need of code, just put some thoughts. I will implement by myself.

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  • No 'Hardware' tab in audio and no profiles

    - by Gene
    If I run the 12.x ubuntu (latest May 2012) from the CD, I get full audio settings, and sound playing in speaker. Profiles let me change analog to digital in/out. Once I run install from the same CD onto the laptop HD, once it boots the first time, after selecting audio settings, there is no 'Hardware' tab and no way to change profiles. Worst part is the audio device is set to SPDIF so nothing comes out of the speakers. Very off how booting off the CD I can get analog audio, and installing to HD and booting seems to limit the profile to something useless. Laptop is a 5 year old Dell D820 with Nvidea 128meg video on a 1920x1200 screen and T7200 CPU. I suspect if I could get the damn HARDWARE tab back in audio settings, I could just select the proper Analog profile - just as is the case if running from a boot CD. Searched the web, no similar problems found... any help appreciated!

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  • Text reverses on remote gnome session

    - by Andrew Stern
    I have two computers running 10.4 . The first machine is a wired desktop with sshd. The second is a wifi connected laptop with the ssh client. When I use my laptop to bring up a remote gnome session to my desktop all the text gets reversed. Steps: 1) login as a user on the laptop to activate the wifi with a stored key. 2) goto a console Ctrl-Alt F1 3) do a xterm -- :1 to bring up a blank graphic session 4) ssh -Y user@desktopmachine gnome-session This shows reversed text and messes up the keyboard so I can't type

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  • Cannot run one of two OS

    - by Nathan
    first i am happy cuz i updated to ubuntu 12.10! yeah The grub had an error, but using this guide https://help.ubuntu.com/community/Boot-Repair i fixed it. yeah again I show you the page that gives me the program http://paste.ubuntu.com/1370085/ I have the system selection screen in violet, but i cannot run Windows XP. Only Ubuntu. When i press enter to start windows, the screen turns black and it returns automatically to the system selection screen. Is just that little problem, i need to use twos OS for job's reason. Thanks in advance and sorry for my little english!

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  • Draw order in XNA

    - by Petr Abdulin
    It is possible to set draw order of a DrawableGameComponent by setting DrawOrder property. But is it possible to set draw order of "main" Game class? I have 2 DrawableGameComponents, and Draw method of a main Game class is called first, while I want it to be the last. Should I just mode all "main" draw code to another component and set it DrawOrder? Answer: seems like I'm just confused myself a little. Black on black, that's why I didn't saw it. Main Draw is called last, as expected.

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  • Hyperion Smart View Assistance

    - by p.anda
    (in via Akhter) Seeking more information or assistance with Hyperion Smart View?  The Oracle Technology Network (OTN) is a great first place to "stop-by".  Here the site provides access to the latest installer, general product documentation as well as Whitepapers, "Whats New" and "Oracle by Example" tutorials: OTN: Overview | Downloads | Documentation | Tutorials  For the latest documentation including Readme, New Features, User's Guide, Developer's Guide and Accessibility Guide visit: Oracle Hyperion Smart View for Office Documentation Release 11.1.2.5 Several "My Oracle Support" Knowledge (KM) Articles are available including: OBIEE 11.1.1.7 - New Features And Recommendations For Working With Microsoft Office [ Doc ID 1558070.1]- How to Integrate OBIEE with Microsoft Office Using Oracle Hyperion Smart View For Office [ Doc ID 1576336.1] - How To Create New Report From Scratch Within Excel Using Smart View [ Doc ID 1576596.1] These along with additional KM articles are being indexed in a Master Note - to keep up to-date with new articles bookmark this index page at: Master Note For Oracle Hyperion Smart View For Office Issues in OBIEE Doc ID 1589028.1

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  • How do I get a Qualcomm Atheros Killer E2200 gigabit ethernet card working on a MSI Z87-GD65?

    - by Travis Allen
    So I literally just built my first computer from scratch and I can't get the network card to work as I've gathered it requires getting some drivers somehow.. Motherboard : MSI Z87-GD65 CPU : Intel Haswell i7 Ubuntu Ver : 12.04 Using the on-board network port Please help I'm about to start crying into my keyboard over this (not really). Any info would be greatly appreciated, also please be very specific as to what I have to do as I have not used Ubuntu very much so talk to me like a child, I won't take offence. Also I've already tried following the instructions here : How do I get a Qualcomm Atheros Killer E2200 gigabit ethernet card working? I don't know if I'm just retarded or am missing something

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  • Passing Parameters Between Web-Services and JSF Pages

    - by shay.shmeltzer
    This is another quick demo that shows a common scenario that combines several demos I did in the past. The scenario – we have two web services, one returns a list of objects, the other allows us to update an object. We want to build a page flow where the first page shows us the list of objects, allows us to select one, and then we can edit that instance in the next page and call the second web service to update our data source. The demo shows: How to select a row and save the object value in a pageFlowScope. (using setPropertyListener). How to create a page that allows me to modify the value of the pageFlowScope object, and how to pass the object as a parameter to the second Web service. Check it out here:

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  • AdWords Keyword Tool planner CPC completely different to real CPC?

    - by steve
    I'm new to AdWords, and trying to figure out the best keywords to use. I go to Adwords Keyword Planner, and typed in an example keyword. It gives me an average CPC of $0.94. But when I go to set up a real campaign and type it the same keyword, I get an error saying 'below first page bid estimate' which is $8.75. What gives? Is there a better way to get more accurate feedback on how much this will cost?

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  • Wireless speed drops over time and doesn't get up if not reconnected

    - by Vili Lehto
    I am using Ubuntu 12.10 64bit and I have a Asus PCE-N15 wireless card(in PCI-E slot). The problem is that first when I connect to my WiFi network the speed is just fine, and actually my link speed never drops, it shows a solid 150mb/s+ link speed and good signal. But the download and upload speeds drop dramatically after couple minutes of use and I have to reconnect to fix this. Network is type IEEE 802.11bgn and uses WPA2/AES encryption. I don't have similar problems on the windows side, and the network is working fine on every other device. iwconfig shows this: wlan0 IEEE 802.11bgn ESSID:"WLAN-AP" Mode:Managed Frequency:2.412 GHz Access Point: 00:1E:AB:05:EF:31 Bit Rate=300 Mb/s Tx-Power=20 dBm Retry long limit:7 RTS thr=2347 B Fragment thr:off Encryption key:off Power Management:off Link Quality=61/70 Signal level=-49 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:2 Missed beacon:0 So the question is: Is there a way to fix this? Thanks in advance.

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  • Looking for information on Scholastic BASIC programming books from the mid-1980s

    - by Jason Berkan
    My very first introduction to programming was in grade school, when I would purchase books full of BASIC code listings from the Scholastic school catalogue. Lately I have been searching teh Internetz for information on these books, but without any success. Does anyone know or remember anything about these books? All I can recall is that they were large paperbacks full of various BASIC code listings, some of which were game like. They all included instructions on how to modify the code listings for the different systems of the day, and I distinctly remember that they would always ask for a number in order to seed the RANDOMIZE command (since I figured out on my own that RANDOMIZE TIMER eliminated the need for the question and answer).

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  • have a missing file, and cant run ubuntu upon start up, and hasnt the flash drive i used didnt work either, any help?

    - by trent
    when I first downloaded Ubuntu to install it, it downloaded quick and caused no problems to my laptop. but then when it came time to install it as one of my operating systems, it wouldn't run because it said a file was missing or damaged. so then I uninstalled it and re-installed it but I still had that same problem. so I tried a flash-drive version but that didn't work either because it wouldn't boot from that, nor would it detect my flash drive, (in this case, an old 4 GB mp3 player). any help or tips and ideas would be great, I just need a decent operating system because windows is getting to be terrible at the moment, just note I wanna run Ubuntu along side windows 8.1

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  • Wireless USB Adapter driver configuration

    - by Jones
    First I would like agree one thing that this is fully for Ubuntu, not for BackTrack. However I'm posting my BackTrack question here since I find similar problems in backtrack forum are being unanswered and Linux/Unix site of StackExchange has very low attraction. I'm having USB wifi adapter (iBall Baton), having chipset RTL8191SU. It displays available wifi networks in Wicd manager. But while trying to connect it gives me bad password. When I'm trying to run airmon-ng it didn't returned me the monitor mode. I tried to replace with Ubuntu 12.10 drivers. But it totally nulled the device functionality. However I restored the drivers. I'm interested to compile drivers as if anyone indicate the methods. Awaiting ideas!

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  • After executing a command in the terminal, I sometimes can't execute another

    - by jreed121
    First off sorry for the noob question, I'm sure it's been asked before but I have no idea how to phrase it eloquently... Sometimes when I open/run/execute (unsure of proper term) an application (?lol) from the terminal like geany ie: geany filename.php or maybe run a node.js script: node server.js The command will execute fine, but I'm then left without the ability to execute any other commands unless I open another terminal. my root@pcname:~$ is gone and when I try typing in something else and hitting Enter it just breaks to the next line. I've noticed that sometimes I can hit CTRL+D and it'll give me my prompt back (sorry is prompt even the right name for it?) So could someone please explain why this is happening and how I can get back to the prompt without opening another terminal. Thanks, and sorry again for my noobery.

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  • How to make openJDK automatically update-alternatives?

    - by cgc512
    Well, I've made a fresh Ubuntu 11.10 install and I installed openJDK 7. It updated alternatives just after installing, so it was all good. Then, I compiled a source and executed it and it didn't worked, then I noticed that java was using the version 1.6, while the javac was 1.7. I thought I had installed it wrong, so I uninstalled it and installed it again. But now, it does not update alternatives automatically (it does it only for javaws). Is there a way to "restart" it so the apt-get does the update-alternatives by itself like the first time? Is it normal that it uses the java 1.6 instead of the java 1.7 when installing openJDK 7? Thank you very much!

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  • New to CG shader programming, what program should I use to write and test them?

    - by Notbad
    I have started witting some shaders. First ones were fairly easy to write in notepad but now I need something with a bit more meat. I have checked rendermonnkey that seems to support CG but it is really old and don't know if it is a good option. On the other hand there exist this FX Composer 2.0 but it seems somthing that could really distract me from learning shaders because it seems a pretty deep program. Are there any other possibilities? There's a really nice alternative to write shaders named ShaderToy but just supports GLSL. Any information will be really welcomed. Thanks in advance.

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  • Assets.getBytes returns null in test environment

    - by ashes999
    I'm using the latest Haxe (2.10), NME (3.4.3), and MUnit. I've written some unit tests that need to fetch bitmap data from SWF symbols. The first step is to actually load the SWF data. To do this, I use NME's getByteArray along with the swf library, like so: var blah:SWF = new SWF(Assets.getBytes("assets/swf/test.swf")); The call to Assets.getBytes returns null when I'm running this under MUnit. When running my actual game code, I'm able to get the byte array (and consequentially, instantiate the SWF class). Am I doing something wrong? What am I missing? Edit: My directory structure is: . (root .\assets .\assets\*.png (other images) .\assets\swf\*.swf (SWFs) .\Source\*.hx (source code) .\Test\*.hx (tests)

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  • #OOW 2012 @PARIS...talking Oracle and Clouds, and Optimized Datacenter

    - by Eric Bezille
    For those of you who want to get most out of Oracle technologies to evolve your IT to the Next Wave, I encourage you to register to the up coming Oracle Optimized Datacenter event that will take place in Paris on November 28th. You will get the opportunity to exchange with Oracle experts and customers having successfully evolve their IT by leveraging Oracle technologies. You will also get the latest news on some of the Oracle systems announcements made during OOW 2012. During this event we will make an update about Oracle and Clouds, from private to public and hybrid models. So in preparing this session, I thought it was a good start to make a status of Cloud Computing in France, and CIO requirements in particular. Starting in 2009 with the first Cloud Camp in Paris, the market has evolved, but the basics are still the same : think hybrid. From Traditional IT to Clouds One size doesn't fit all, and for big companies having already an IT in place, there will be parts eligible to external (public) cloud, and parts that would be required to stay inside the firewalls, so ability to integrate both side is key.  None the less, one of the major impact of Cloud Computing trend on IT, reported by Forrester, is the pressure it makes on CIO to evolve towards the same model that end-users are now used to in their day to day life, where self-service and flexibility are paramount. This is what is driving IT to transform itself toward "a Global Service Provider", or for some as "IT "is" the Business" (see : Gartner Identifies Four Futures for IT and CIO), and for both models toward a Private Cloud Service Provider. In this journey, there is still a big difference between most of existing external Cloud and a firm IT : the number of applications that a CIO has to manage. Most cloud providers today are overly specialized, but at the end of the day, there are really few business processes that rely on only one application. So CIOs has to combine everything together external and internal. And for the internal parts that they will have to make them evolve to a Private Cloud, the scope can be very large. This will often require CIOs to evolve from their traditional approach to more disruptive ones, the time has come to introduce new standards and processes, if they want to succeed. So let's have a look at the different Cloud models, what type of users they are addressing, what value they bring and most importantly what needs to be done by the  Cloud Provider, and what is left over to the user. IaaS, PaaS, SaaS : what's provided and what needs to be done First of all the Cloud Provider will have to provide all the infrastructure needed to deliver the service. And the more value IT will want to provide, the more IT will have to deliver and integrate : from disks to applications. As we can see in the above picture, providing pure IaaS, left a lot to cover for the end-user, that’s why the end-user targeted by this Cloud Service is IT people. If you want to bring more value to developers, you need to provide to them a development platform ready to use, which is what PaaS is standing for, by providing not only the processors power, storage and OS, but also the Database and Middleware platform. SaaS being the last mile of the Cloud, providing an application ready to use by business users, the remaining part for the end-users being configuring and specifying the application for their specific usage. In addition to that, there are common challenges encompassing all type of Cloud Services : Security : covering all aspect, not only of users management but also data flows and data privacy Charge back : measuring what is used and by whom Application management : providing capabilities not only to deploy, but also to upgrade, from OS for IaaS, Database, and Middleware for PaaS, to a full Business Application for SaaS. Scalability : ability to evolve ALL the components of the Cloud Provider stack as needed Availability : ability to cover “always on” requirements Efficiency : providing a infrastructure that leverage shared resources in an efficient way and still comply to SLA (performances, availability, scalability, and ability to evolve) Automation : providing the orchestration of ALL the components in all service life-cycle (deployment, growth & shrink (elasticity), upgrades,...) Management : providing monitoring, configuring and self-service up to the end-users Oracle Strategy and Clouds For CIOs to succeed in their Private Cloud implementation, means that they encompass all those aspects for each component life-cycle that they selected to build their Cloud. That’s where a multi-vendors layered approach comes short in terms of efficiency. That’s the reason why Oracle focus on taking care of all those aspects directly at Engineering level, to truly provide efficient Cloud Services solutions for IaaS, PaaS and SaaS. We are going as far as embedding software functions in hardware (storage, processor level,...) to ensure the best SLA with the highest efficiency. The beauty of it, as we rely on standards, is that the Oracle components that you are running today in-house, are exactly the same that we are using to build Clouds, bringing you flexibility, reversibility and fast path to adoption. With Oracle Engineered Systems (Exadata, Exalogic & SPARC SuperCluster, more specifically, when talking about Cloud), we are delivering all those components hardware and software already engineered together at Oracle factory, with a single pane of glace for the management of ALL the components through Oracle Enterprise Manager, and with high-availability, scalability and ability to evolve by design. To give you a feeling of what does that bring in terms just of implementation project timeline, for example with Oracle SPARC SuperCluster, we have a consistent track of record to have the system plug into existing Datacenter and ready in a week. This includes Oracle Database, OS, virtualization, Database Storage (Exadata Storage Cells in this case), Application Storage, and all network configuration. This strategy enable CIOs to very quickly build Cloud Services, taking out not only the complexity of integrating everything together but also taking out the automation and evolution complexity and cost. I invite you to discuss all those aspect in regards of your particular context face2face on November 28th.

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  • Refactor or Concentrate on Completing App

    - by Jiew Meng
    Would you refactor your app as you go or focus on completing app first? Refactoring will mean progress of app app will slow down. Completing app will mean you get a possibly very hard to maintain app later on? The app is a personal project. I don't really know how to answer "What drives the functionality and design", but I guess it's to solve inefficiencies in current software out there. I like minimal easy to use software too. So I am removing some features and add some that I feel will help.

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  • JPRT: A Build & Test System

    - by kto
    DRAFT A while back I did a little blogging on a system called JPRT, the hardware used and a summary on my java.net weblog. This is an update on the JPRT system. JPRT ("JDK Putback Reliablity Testing", but ignore what the letters stand for, I change what they mean every day, just to annoy people :\^) is a build and test system for the JDK, or any source base that has been configured for JPRT. As I mentioned in the above blog, JPRT is a major modification to a system called PRT that the HotSpot VM development team has been using for many years, very successfully I might add. Keeping the source base always buildable and reliable is the first step in the 12 steps of dealing with your product quality... or was the 12 steps from Alcoholics Anonymous... oh well, anyway, it's the first of many steps. ;\^) Internally when we make changes to any part of the JDK, there are certain procedures we are required to perform prior to any putback or commit of the changes. The procedures often vary from team to team, depending on many factors, such as whether native code is changed, or if the change could impact other areas of the JDK. But a common requirement is a verification that the source base with the changes (and merged with the very latest source base) will build on many of not all 8 platforms, and a full 'from scratch' build, not an incremental build, which can hide full build problems. The testing needed varies, depending on what has been changed. Anyone that was worked on a project where multiple engineers or groups are submitting changes to a shared source base knows how disruptive a 'bad commit' can be on everyone. How many times have you heard: "So And So made a bunch of changes and now I can't build!". But multiply the number of platforms by 8, and make all the platforms old and antiquated OS versions with bizarre system setup requirements and you have a pretty complicated situation (see http://download.java.net/jdk6/docs/build/README-builds.html). We don't tolerate bad commits, but our enforcement is somewhat lacking, usually it's an 'after the fact' correction. Luckily the Source Code Management system we use (another antique called TeamWare) allows for a tree of repositories and 'bad commits' are usually isolated to a small team. Punishment to date has been pretty drastic, the Queen of Hearts in 'Alice in Wonderland' said 'Off With Their Heads', well trust me, you don't want to be the engineer doing a 'bad commit' to the JDK. With JPRT, hopefully this will become a thing of the past, not that we have had many 'bad commits' to the master source base, in general the teams doing the integrations know how important their jobs are and they rarely make 'bad commits'. So for these JDK integrators, maybe what JPRT does is keep them from chewing their finger nails at night. ;\^) Over the years each of the teams have accumulated sets of machines they use for building, or they use some of the shared machines available to all of us. But the hunt for build machines is just part of the job, or has been. And although the issues with consistency of the build machines hasn't been a horrible problem, often you never know if the Solaris build machine you are using has all the right patches, or if the Linux machine has the right service pack, or if the Windows machine has it's latest updates. Hopefully the JPRT system can solve this problem. When we ship the binary JDK bits, it is SO very important that the build machines are correct, and we know how difficult it is to get them setup. Sure, if you need to debug a JDK problem that only shows up on Windows XP or Solaris 9, you'll still need to hunt down a machine, but not as a regular everyday occurance. I'm a big fan of a regular nightly build and test system, constantly verifying that a source base builds and tests out. There are many examples of automated build/tests, some that trigger on any change to the source base, some that just run every night. Some provide a protection gateway to the 'golden' source base which only gets changes that the nightly process has verified are good. The JPRT (and PRT) system is meant to guard the source base before anything is sent to it, guarding all source bases from the evil developer, well maybe 'evil' isn't the right word, I haven't met many 'evil' developers, more like 'error prone' developers. ;\^) Humm, come to think about it, I may be one from time to time. :\^{ But the point is that by spreading the build up over a set of machines, and getting the turnaround down to under an hour, it becomes realistic to completely build on all platforms and test it, on every putback. We have the technology, we can build and rebuild and rebuild, and it will be better than it was before, ha ha... Anybody remember the Six Million Dollar Man? Man, I gotta get out more often.. Anyway, now the nightly build and test can become a 'fetch the latest JPRT build bits' and start extensive testing (the testing not done by JPRT, or the platforms not tested by JPRT). Is it Open Source? No, not yet. Would you like to be? Let me know. Or is it more important that you have the ability to use such a system for JDK changes? So enough blabbering on about this JPRT system, tell me what you think. And let me know if you want to hear more about it or not. Stay tuned for the next episode, same Bloody Bat time, same Bloody Bat channel. ;\^) -kto

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  • MathType and LibreOffice Math comparison

    - by Agmenor
    In my office my team and I are going to type texts in the future which will include mathematical signs. Two programs are being proposed: LibreOffice Writer + Math or Microsoft Office + MathType. I would like to advocate for the first solution, but I need to know what technical advantages and disadvantages each program has. Compatibility with Ubuntu is an evident and important characteristic for LibreOffice, but could you give some other aspects? As a side question, do you advice any other program, even if not WYSIWYG and thus not my preference in this case?

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  • Thread.Interrupt Is Evil

    - by Alois Kraus
    Recently I have found an interesting issue with Thread.Interrupt during application shutdown. Some application was crashing once a week and we had not really a clue what was the issue. Since it happened not very often it was left as is until we have got some memory dumps during the crash. A memory dump usually means WindDbg which I really like to use (I know I am one of the very few fans of it).  After a quick analysis I did find that the main thread already had exited and the thread with the crash was stuck in a Monitor.Wait. Strange Indeed. Running the application a few thousand times under the debugger would potentially not have shown me what the reason was so I decided to what I call constructive debugging. I did create a simple Console application project and try to simulate the exact circumstances when the crash did happen from the information I have via memory dump and source code reading. The thread that was  crashing was actually MS code from an old version of the Microsoft Caching Application Block. From reading the code I could conclude that the main thread did call the Dispose method on the CacheManger class which did call Thread.Interrupt on the cache scavenger thread which was just waiting for work to do. My first version of the repro looked like this   static void Main(string[] args) { Thread t = new Thread(ThreadFunc) { IsBackground = true, Name = "Test Thread" }; t.Start(); Console.WriteLine("Interrupt Thread"); t.Interrupt(); } static void ThreadFunc() { while (true) { object value = Dequeue(); // block until unblocked or awaken via ThreadInterruptedException } } static object WaitObject = new object(); static object Dequeue() { object lret = "got value"; try { lock (WaitObject) { } } catch (ThreadInterruptedException) { Console.WriteLine("Got ThreadInterruptException"); lret = null; } return lret; } I do start a background thread and call Thread.Interrupt on it and then directly let the application terminate. The thread in the meantime does plenty of Monitor.Enter/Leave calls to simulate work on it. This first version did not crash. So I need to dig deeper. From the memory dump I did know that the finalizer thread was doing just some critical finalizers which were closing file handles. Ok lets add some long running finalizers to the sample. class FinalizableObject : CriticalFinalizerObject { ~FinalizableObject() { Console.WriteLine("Hi we are waiting to finalize now and block the finalizer thread for 5s."); Thread.Sleep(5000); } } class Program { static void Main(string[] args) { FinalizableObject fin = new FinalizableObject(); Thread t = new Thread(ThreadFunc) { IsBackground = true, Name = "Test Thread" }; t.Start(); Console.WriteLine("Interrupt Thread"); t.Interrupt(); GC.KeepAlive(fin); // prevent finalizing it too early // After leaving main the other thread is woken up via Thread.Abort // while we are finalizing. This causes a stackoverflow in the CLR ThreadAbortException handling at this time. } With this changed Main method and a blocking critical finalizer I did get my crash just like the real application. The funny thing is that this is actually a CLR bug. When the main method is left the CLR does suspend all threads except the finalizer thread and declares all objects as garbage. After the normal finalizers were called the critical finalizers are executed to e.g. free OS handles (usually). Remember that I did call Thread.Interrupt as one of the last methods in the Main method. The Interrupt method is actually asynchronous and does wake a thread up and throws a ThreadInterruptedException only once unlike Thread.Abort which does rethrow the exception when an exception handling clause is left. It seems that the CLR does not expect that a frozen thread does wake up again while the critical finalizers are executed. While trying to raise a ThreadInterrupedException the CLR goes down with an stack overflow. Ups not so nice. Why has this nobody noticed for years is my next question. As it turned out this error does only happen on the CLR for .NET 4.0 (x86 and x64). It does not show up in earlier or later versions of the CLR. I have reported this issue on connect here but so far it was not confirmed as a CLR bug. But I would be surprised if my console application was to blame for a stack overflow in my test thread in a Monitor.Wait call. What is the moral of this story? Thread.Abort is evil but Thread.Interrupt is too. It is so evil that even the CLR of .NET 4.0 contains a race condition during the CLR shutdown. When the CLR gurus can get it wrong the chances are high that you get it wrong too when you use this constructs. If you do not believe me see what Patrick Smacchia does blog about Thread.Abort and List.Sort. Not only the CLR creators can get it wrong. The BCL writers do sometimes have a hard time with correct exception handling as well. If you do tell me that you use Thread.Abort frequently and never had problems with it I do suspect that you do not have looked deep enough into your application to find such sporadic errors.

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