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  • VLC - Play two mp3s simultaneously from command line

    - by raoulcousins
    I'm using VLC 2.0.8 on Windows 7. How do I play two mp3s simultaneously from the command line (command line because to write a batch script that launches the mp3s)? I've tried vlc 1.mp3 2.mp3 and vlc 1.mp3 --input-slave 2.mp3 (I've seen the second one as a way to play a video file and a separate audio file simultaneously). Both of these just launch 1.mp3. Not important, but if you're wondering, the mp3s are respectively cafe sounds and rain sounds, so I can play sounds similar to those found at http://rainycafe.com/ without having to launch a browser.

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  • Limiting and redirect port access with useragent

    - by linuxcore
    I'm trying to write iptables string match rule To block http://domain.com:8888 and https://domain.com:8888 when it matches the supplied string in the rule. And another rule to redirect the ports also from 8888 to 7777 I tried following rules but unfortunately didn't work iptables -A INPUT -p tcp -s 0.0.0.0/0 -m string --string linuxcore --algo bm --sport 8888 -j DROP iptables -t raw -A PREROUTING -m string --algo bm --string linuxcore -p tcp -i eth0 --dport 8888 -j DROP iptables -t nat -A PREROUTING -p tcp --dport 8888 -m string --algo bm --string "linuxcore" -j REDIRECT --to-port 7777 iptables -A INPUT -t nat -p tcp --dport 8888 -m string --algo bm --string "linuxcore" -j DROP I want to do this from iptables not the webserver because the server may not have a webserver and those ports are working on internal proxy or something like ..etc

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  • No Thank You &ndash; Yours Truly &ndash; F#

    - by MarkPearl
    I am plodding along with my F# book. I have reached the part where I know enough about the syntax of the language to understand something if I read it – but not enough about the language to be productive and write something useful. A bit of a frustrating place to be. Needless to say when you are in this state of mind – you end up paging mindlessly through chapters of my F# book with no real incentive to learn anything until you hit “Exceptions”. Raising an exception explicitly So lets look at raising an exception explicitly – in C# we would throw the exception, F# is a lot more polite instead of throwing the exception it raises it, … (raise (System.InvalidOperationException("no thank you"))) quite simple… Catching an Exception So I would expect to be able to catch an exception as well – lets look at some C# code first… try { Console.WriteLine("Raise Exception"); throw new InvalidOperationException("no thank you"); } catch { Console.WriteLine("Catch Exception and Carry on.."); } Console.WriteLine("Carry on..."); Console.ReadLine();   The F# equivalent would go as follows… open System; try Console.WriteLine("Raise Exception") raise (System.InvalidOperationException("no thank you")) with | _ -> Console.WriteLine("Catch Exception and Carry on..") Console.WriteLine("Carry on...") Console.ReadLine();   In F# there is a “try, with” and a “try finally” Finally… In F# there is a finally block however the “with” and “finally” can’t be combined. open System; try Console.WriteLine("Raise Exception") raise (System.InvalidOperationException("no thank you")) finally Console.WriteLine("Finally carry on...") Console.ReadLine()

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  • Apache expands REQUEST_FILENAME with filetype

    - by Lauer
    I have a .htaccess fil on a Apache22 server. RewriteEngine On RewriteBase / RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule ^(.+)$ /index.php?p=$1 [L] The idea is when the request is /testpage it should be rewritten to /index.php?p=testpage. The problem is that apache does a write before my file, so the actually request is testpage.xml which actually does exists. Therefore, the first RewriteCond is newer true, and my rewrite rule is never applied on the /testpage request. There server should be a standard setup on a FreeBSD server. I know this work on other servers.

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  • Adding chinese keyboard

    - by user63434
    I am trying to find an .adm or GPO settings so when any users login to the 2003/2008 server using Windows 7/windows xp pro client it will add the keyboard Chinese PRC (one of the inputs that is listed) in the language bar. Any ideas or if this is possible much apprieciated. Thanks Thanks, it's a client login from a network to the server. Your adm is for setting up a UK keyboard, I think I have a usa keyboard adm, I have downloaded google pinyin and I need to set it up for PRC (google pinyin) input option under language also any ideas how to write an adm for this as I am not sure how to get the codes etc you have. Thanks

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  • LINQ to Twitter Maintenance Feedback

    - by Joe Mayo
    Originally posted on: http://geekswithblogs.net/WinAZ/archive/2013/06/16/linq-to-twitter-maintenance-feedback.aspxIt’s always fun to receive positive feedback on your work. If you receive a sufficient amount of positive feedback, you know you’re doing something right. Sometimes, people provide negative feedback too. There are a couple ways to handle it: come back fighting or engage for clarification. The way you handle the negative feedback depends on what your goals are. Feedback Approaches If you know the feedback is incorrect and you need to promote your idea or product, you might want to come back fighting. The feedback might just be comments by a troll or competitor wanting to spread FUD. However, this could be the totally wrong approach if you misjudge the source and intentions of the feedback. In a lot of cases, feedback is a golden opportunity. Sometimes, a problem exists that you either don’t know about or don’t realize the true impact of the problem. If you decide to come back fighting, you might loose the opportunity to learn something new. However, if you engage the person providing the feedback, looking for clarification, you might learn something very important. Negative feedback and it’s clarification can lead to the collection of useful and actionable data. In my case, something that prompted this blog post, I noticed someone who tweeted a negative comment about LINQ to Twitter. Normally, any less than stellar comments are usually from folks that need help – so I help if I can. This was different. I was like “Don’t use LINQ to Twitter”. This is an open source project, the comment didn’t come from a competing project, and  sounded more like an expression of frustration. So I engaged. Not only did the person respond, but I got some decent quality feedback. What’s also interesting is a couple other side conversations sprouted on the subject, which gave me more useful data. LINQ to Twitter Thread Actions Essentially, this particular issue centered around maintenance. There are actually several sub-issues at play here: dependencies, error handling, debugging, and visibility. I’ll describe each one and my interpretation. Dependencies Dependencies are where a library has references to other libraries. This means that when you build your application, you need DLLs for the entire dependency graph for your application. There are several potential problems with this that include more libraries for configuration management, potential versioning mismatches, and lack of cross-platform support. In the early days of LINQ to Twitter, I allowed developers to contribute and add dependencies, but it became very problematic (for reasons stated). It was like a ball and chain that kept me from moving forward. So, I refactored and pulled other open-source into my project to eliminate external dependencies. This lets me fix the code in my project without relying on someone else to upgrade or fix their DLL. The motivation for this was from early negative feedback that translated as important data and acted on it. Today, LINQ to Twitter has zero dependencies. Note: Rejecting good code from community members who worked hard to make your project better is a painful experience in itself. I have to point out that any contribution was not in vain because they had a positive influence on my subsequent refactoring that resulted in a better developer experience. Error Handling Error handling has been a problem in the past. I have this combination of supporting both synchronous and asynchronous (APM) processing that can be complex at times. Within the last 6 months, I did a fair amount of refactoring to detect errors and process them properly. I also refactored TwitterQueryException so it includes important data from Twitter. During this refactoring, I’ve made breaking changes that I felt would improve the development experience (small things like renaming a callback property to Exception, rather than Error). I think the async error handling is much better than it was a year ago. For all the work I’ve done, there is more to do. I think that a combination of more error handling support, e.g. improving semantics, and education through documentation and samples will improve the error handling story. Because of what I’ve done so far, it isn’t bad, but I see opportunities for improvement. Debugging Debugging can be painful. Here’s why: you have multiple layers of technology to navigate and figure out where the real problem is – Twitter API, Security, HTTP, LINQ to Twitter, and application. You can probably add your own nuances to that list, but the point is that debugging in this environment can be complex. I think that my plans for error handling will contribute to making the debugging process easier. However, there’s more I can do in the way of documentation and guidance. Some of the questions to be answered revolve around when something goes wrong, how does the developer figure out that there is a problem, what the problem is, and what to do about it. One example that has gone a long way to helping LINQ to Twitter developers is the 401 FAQ. A 401 Unauthorized is the error that the Twitter API returns when a use isn’t able to authenticate and is one of the most difficult problems faced by LINQ to Twitter developers. What I did was read guidance from Twitter and collect techniques from my own development and actions helping other developers to compile an extensive list of reasons for the 401 and ways to fix the problem. At one time, over half of the questions I answered in the forums were to help solve 401 issues. After publishing the 401 FAQ, I rarely get a 401 question and it’s because the person didn’t know about the FAQ. If the person is too lazy to read the FAQ, that’s not my issue, but the results in support issues have been dramatic. I think debugging can benefit from the education and documentation approach, but I’m always open to suggestions on whatever else I can do. Visibility Visibility is a nuance of the error handling/debugging discussion but is deeply rooted in comfort and control. The questions to ask in this area are what is happening as my code runs and how testable is the code. In support of these areas, LINQ to Twitter does have logging and TwitterContext properties that help see what’s happening on requests. The logging functionality allows any developer to connect a TextWriter to the Log property of TwitterContext to see what’s happening. Further, TwitterContext has a Headers property to see the headers Twitter returns and a RawResults property to show the Json string Twitter returns. From a testing perspective, I’ve been able to write hundreds of unit tests, over 600 when this post is published, and growing. If you write your own library, you have full control over all of these aspects. The tradeoff here is that while you have access to the LINQ to Twitter source code and modify it for all the visibility, LINQ to Twitter *will* change (which is good) and you will have to figure out how to merge that with your changes (which is hard). The fact is that this is a limitation of any 3rd party library, not just LINQ to Twitter. So, it’s a design decision where the tradeoff is between control and productivity. That said, there are things I can do with LINQ to Twitter to make the visibility story more compelling. I think there are opportunities to improve diagnostics. This would be a ton of work because it would need to provide multi-level logging that can be tuned for production and support any logging provider you want to attach. I’ve considered approaches such as how the new Semantic Logging application block connects to Windows Error Reporting as a potential target. Whatever I do would need to be extensible without creating native external dependencies. e.g. how many 3rd party libraries force a dependency on a logging framework that you don’t use. So, this won’t be an easy feat, but I believe it can be part of the roadmap. I think that a lot of developers are unaware of existing visibility features, so the first step would be to provide more documentation and guidance. My thought are that this would lead to more feedback that will help improve this area. Summary Recent feedback highlights some of items that are important to LINQ to Twitter developers, such as dependencies, error handling, debugging, and visibility. I know that there are maintenance issues that have been problems for LINQ to Twitter developers in the past. I’ve done a lot of work in this area, such as improving error handling, adding visibility features, and providing extensive API documentation. That said, there is more to be done to make LINQ to Twitter the best Twitter API experience available for .NET developers and I welcome anyone’s thoughts on what I’ve written here or new improvements. @JoeMayo

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  • central log-server with auditdisp

    - by johan
    I want to setup a central log-server. The log-server is running with debian 6.0.6 and the audit daemon is installed in version 1.7.13-1. The Clients are running with Red Hat 5.5 and they connect to the log-server via audispd. The connection works fine and i get all messages from each node. My questions is: is it possible that the auditd daemon from the log server write the messages from each node in a separate file? I try to transfer the messages via the syslog daemon, that works but i can not use tools like ausearch to analyze these log-files.

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  • Installing isolated instance of MySQL on Windows using silent install with .msi

    - by Abram
    I'm trying to write an installer for an internal application we wrote. After it installs our application it then installs MySQL using the .msi installer in silent mode. I specify the install dir and data dir to that of a directory within my application's install directory, such as: msiexec /i @@MYSQL_INSTALLER_FILE@@ /qn INSTALLDIR="@@INSTALL_DIR@@\MySQL\" DATADIR="@@INSTALL_DIR@@\MySQL\" USERNAME="@@DB_USER@@" PASSWORD="@@DB_PASS@@" (the @@variable@@'s are replace by my installer routine using InstallJammer) Once installed, I use mysqld.exe to install a windows service with a custom service name and defaults file like so: mysqld.exe --install CustomMySQL --defaults-file="@@INSTALL_DIR@@\MySQL\my.ini" This works fine as long as there is not already another instance of MySQL installed. If there is it silently fails to install MySQL. Running the msi installer manually (double-click) shows an error that a previous version is already installed and just aborts. Is there a way to automate installing MySQL as an isolated instance, regardless of whether another version/instance is already installed?

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  • Ubuntu boots in read-only filesystem after upgrade!

    - by akatzbreaker
    I got a serious problem here: I recently upgraded to the Latest Version of Ubuntu. Now, I boot to my Ubuntu Partition, and I get a Low-Graphics error! I boot to a Recovery-Mode to see what the Problem is. Then, I try to Fix any Damaged Packages, to run fsck but nothing solved the Problem. Then, from the Recovery Menu, I open a Root Shell. I try to create a File and I understand that the Filesystem is Read-Only. Then, I run: mount -o remount,rw / and it Worked for that Terminal Session! When I go back to recovery, I select to resume Boot Normally but I get the Same Error! a I also tried to Boot to my Root Shell again, remount as Read-Write and Start Gnome from there. It Worked! (But the user is ROOT, and is quite Dangerous!) However, I can't do all this proccess at every boot! Any Solution? (Note that when I try to create a new File in my Ubuntu Partition from another OS, I don't get any Errors!)

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  • How to justify rewriting/revamping legacy software in a business case?

    - by sxthomson
    I work for a great little software company which makes good revenue from our main software package. The problem for me is that it's almost unmaintainable. It's written in Delphi 7 (has upgraded versions over time) and has been worked on by a lot of developers over the past 20 or so years. The software lacks any meaningful architecture - there's no object orientation whatsoever, horrible amounts of cyclical dependencies and an over-reliance on global variables to name just a few things. Another huge thing for me is Delphi 7 does NOT support 64-bit. The problem here for me is that my management team don't care about technical things, they want to know why they should care. Obviously that's expected, so what I'm asking here is for some guidance, or tales, or pitfalls about this kind of thing. There's a few things I would love to include, namely for me, the length of time taken to debug/write a feature in "legacy" code, versus coherent, well structured OO code. Does anyone know of any blog posts or the like where this is talked about? For us in the company this is a huge reason. Despite being decent developers we feel like writing a new feature is just piling more rubbish on top. On top of that, even for me who has a decent level of understanding of the code, changing things is infuriating - a small change can have a ridiculous domino effect. Anyone have any experiences they'd like to share?

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  • Unnamed Refactoring

    - by Liam McLennan
    This post is a message in a bottle. It cast it into the sea in the hope that it will one day return to me, stuffed to the cork with enlightenment. Yesterday I  tweeted, what is the name of the pattern where you replace a multi-way conditional with an associative array? I said ‘pattern’ but I meant ‘refactoring’. Anyway, no one replied so I will describe the refactoring here. Programmers tend to think imperatively, which leads to code such as: public int GetPopulation(string country) { if (country == "Australia") { return 22360793; } else if (country == "China") { return 1324655000; } else if (country == "Switzerland") { return 7782900; } else { throw new Exception("What ain't no country I ever heard of. They speak English in what?"); } } which is horrid. We can write a cleaner version, replacing the multi-way conditional with an associative array, treating the conditional as data: public int GetPopulation(string country) { if (!Populations.ContainsKey(country)) throw new Exception("The population of " + country + " could not be found."); return Populations[country]; } private Dictionary<string, int> Populations { get { return new Dictionary<string, int> { {"Australia", 22360793}, {"China", 1324655000}, {"Switzerland", 7782900} }; } } Does this refactoring already have a name? Otherwise, I propose Replace multi-way conditional with associative array

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  • Is a PCIE X1 card for USB 3.0 worth it?

    - by lelouch
    I have a portable HDD on USB 3.0, and soon I'll have a 32gb flash drive on USB 3.0 as well. My motherboard is pretty old - and the next time I'll upgrade it is when I get a new CPU/mobo/ram. Slots on my mobo: PCIE X16 - For my GTX 260 2xPCI PCIE X1 I'm considering purchasing a PCI express X1 card like this - http://www.ebay.com.au/itm/PC-Laptop-2-USB3-0-Ports-PCI-E-PCI-Express-X1-Card-New-/280772000446?pt=AU_Networking&hash=item415f50babe Now the question: What are realistic (read/write) speeds I'll get in this setup, assuming I have 1 USB 3 device connected at a time, and the bottleneck is the PCIE?

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  • More Denali Execution Plan Warning Goodies

    - by Dave Ballantyne
    In my last blog, I showed how the execution plan in denali has been enhanced by 2 new warnings ,conversion affecting cardinality and conversion affecting seek, which are shown when a data type conversion has happened either implicitly or explicitly. That is not all though, there is more .  Also added are two warnings when performance has been affected due to memory issues. Memory spills to tempdb are a costly operation and happen when SqlServer is under memory pressure and needs to free some up. For a long time you have been able to see these as warnings in a profiler trace as a sort or hash warning event,  but now they are included right in the execution plan.  Not only that but also you can see which operator caused the spill , not just which statement.  Pretty damn handy. Another cause of performance problems relating to memory are memory grant waits.  Here is an informative write up on them,  but simply speaking , SQLServer has to allocate a certain amount of memory for each statement. If it is unable to you get a “memory grant wait”.  Once again there are other methods of analyzing these,  but the plan now shows these too. Don't worry that’s not real production code There is one other new warning that is of interest to me, “Unmatched Indexes”.  Once I find out the conditions under which that fires ill blog about it.

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  • What is the recommended way to empty a SSD?

    - by Lekensteyn
    I've just received my new SSD since the old one died. This Intel 320 SSD supports TRIM. For testing purposes, my dealer put malware, err, Windows on it. I want to get rid of it and install Kubuntu on it. It does not have to be a "secure wipe", I just need the empty the disk in the mosy healthy way. I believe that dd if=/dev/zero of=/dev/sda just fills the blocks with zeroes and thereby taking another write (correct me if I'm wrong). I've seen the answer How to enable TRIM, but it looks like it's suited for clearing empty blocks, not wiping the disk. hdparm seems to be the program to do it, but I'm not sure if it clears the disk OR cleans empty blocks. From its manual page: --trim-sector-ranges For Solid State Drives (SSDs). EXCEPTIONALLY DANGEROUS. DO NOT USE THIS OPTION!! Tells the drive firmware to discard unneeded data sectors, destroying any data that may have been present within them. This makes those sectors available for immediate use by the firmware's garbage collection mechanism, to improve scheduling for wear-leveling of the flash media. This option expects one or more sector range pairs immediately after the option: an LBA starting address, a colon, and a sector count, with no intervening spaces. EXCEPTIONALLY DANGEROUS. DO NOT USE THIS OPTION!! E.g. hdparm --trim-sector-ranges 1000:4 7894:16 /dev/sdz How can I make all blocks appear as empty using TRIM?

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  • How to unit test models in MVC / MVR app?

    - by BBnyc
    I'm building a node.js web app and am trying to do so for the first time in a test driven fashion. I'm using nodeunit for testing, which I find allows me to write tests quickly and painlessly. In this particular app, the heavy lifting primarily involves translating SQL data into complex Javascript object and serving them to the front-end via json. Likewise, the app also spends a great deal of code validating and translating complex, multidimensional Javascript objects it receives from the front-end into SQL rows. Hence I have used a fat model design for the app -- most of the real code resides in the models, where the data translation happens. What's the best approach to test such models with unit tests? I mean in particular the methods that have create javascript objects from the SQL rows and serve them to the front-end. Right now what I'm doing is making particular requests of my models with the unit tests and checking the returned data for all of the fields that should be there. However I have a suspicion that this is not the most robust kind of testing I could be doing. My current testing design also means I have to package my app code with some dummy data so that my tests can anticipate the kind of data that the app should be returning when tests run.

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  • Recommended formats to store bitmaps in memory?

    - by Geotarget
    I'm working with general purpose image rendering, and high-performance image processing, and so I need to know how to store bitmaps in-memory. (24bpp/32bpp, compressed/raw, etc) I'm not working with 3D graphics or DirectX / OpenGL rendering and so I don't need to use graphics card compatible bitmap formats. My questions: What is the "usual" or "normal" way to store bitmaps in memory? (in C++ engines/projects?) How to store bitmaps for high-performance algorithms, such that read/write times are the fastest? (fixed array? with/without padding? 24-bpp or 32-bpp?) How to store bitmaps for applications handling a lot of bitmap data, to minimize memory usage? (JPEG? or a faster [de]compression algorithm?) Some possible methods: Use a fixed packed 24-bpp or 32-bpp int[] array and simply access pixels using pointer access, all pixels are allocated in one continuous memory chunk (could be 1-10 MB) Use a form of "sparse" data storage so each line of the bitmap is allocated separately, reusing more memory and requiring smaller contiguous memory segments Store bitmaps in its compressed form (PNG, JPG, GIF, etc) and unpack only when its needed, reducing the amount of memory used. Delete the unpacked data if its not used for 10 secs.

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  • Can I create a DC without a DNS Server?

    - by onik
    So as the title says, I need to promote a standalone Win2008R2 server to a Domain Controller, and I don't a DNS Server (I think), as there will be no clients connected to the domain, it will be only used for Remote Desktop Services. Yes, I know, it's considered bad practice to install other roles on the DC, but in this case, it's necessary. Do I need to install the DNS Server, and if I do, how to make it as transparent as possible? EDIT: Seems that I need to install the DNS Server, so I can I configure it not to mess up my entire domain? For example: The server I need to promote is rdc.mydomain.com, and it has an A entry to it's IP in the current DNS, while other servers under mydomain.com are running Linux and don't need to know anything about this Windows box. The domain uses a third-party DNS and all edits and updates need to be done via a separate web page, our servers don't have write/update access.

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  • Tail-recursive implementation of take-while

    - by Giorgio
    I am trying to write a tail-recursive implementation of the function take-while in Scheme (but this exercise can be done in another language as well). My first attempt was (define (take-while p xs) (if (or (null? xs) (not (p (car xs)))) '() (cons (car xs) (take-while p (cdr xs))))) which works correctly but is not tail-recursive. My next attempt was (define (take-while-tr p xs) (let loop ((acc '()) (ys xs)) (if (or (null? ys) (not (p (car ys)))) (reverse acc) (loop (cons (car ys) acc) (cdr ys))))) which is tail recursive but needs a call to reverse as a last step in order to return the result list in the proper order. I cannot come up with a solution that is tail-recursive, does not use reverse, only uses lists as data structure (using a functional data structure like a Haskell's sequence which allows to append elements is not an option), has complexity linear in the size of the prefix, or at least does not have quadratic complexity (thanks to delnan for pointing this out). Is there an alternative solution satisfying all the properties above? My intuition tells me that it is impossible to accumulate the prefix of a list in a tail-recursive fashion while maintaining the original order between the elements (i.e. without the need of using reverse to adjust the result) but I am not able to prove this. Note The solution using reverse satisfies conditions 1, 3, 4.

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  • "The program is too big to fit in memory" problem?!!

    - by user47038
    Please help me!!! This is most amazing error that i have ever had, we write 100 CD, in these CDs we got one setup.exe file that autorun. in some of these CDs when I explore the cd the setup.exe file become the command prompt file and give me above error. and when I reset the system and put it in another pc it`s ok. if I reset the first pc the autorun.exe run. so I change it different computer, randomly get this problem. I am sure about the virus, because I checked on different pcs and with fully update definition so someone tell me what happen?

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  • Creating shooting arrow class [on hold]

    - by I.Hristov
    OK I am trying to write an XNA game with one controllable by the player entity, while the rest are bots (enemy and friendly) wondering around and... shooting each other from range. Now the shooting I suppose should be done with a separate class Arrow (for example). The resulting object would be the arrow appearing on screen moving from shooting entity to target entity. When target is reached arrow is no longer active, probably removed from the list. I plan to make a class with fields: Vector2 shootingEntity; Vector2 targetEntity; float arrowSpeed; float arrowAttackSpeed; int damageDone; bool isActive; Then when enemy entities get closer than a int rangeToShoot (which each entity will have as a field/prop) I plan to make a list of arrows emerging from each entity and going to the closest opposite one. I wonder if that logic will enable me later to make possible many entities to be able to shoot independently at different enemy entities at the same time. I know the question is broad but it would be wise to ask if the foundations of the idea are correct.

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  • Are there design patterns or generalised approaches for particle simulations?

    - by romeovs
    I'm working on a project (for college) in C++. The goal is to write a program that can more or less simulate a beam of particles flying trough the LHC synchrotron. Not wanting to rush into things, me and my team are thinking about how to implement this and I was wondering if there are general design patterns that are used to solve this kind of problem. The general approach we came up with so far is the following: there is a World that holds all objects you can add objects to this world such as Particle, Dipole and Quadrupole time is cut up into discrete steps, and at each point in time, for each Particle the magnetic and electric forces that each object in the World generates are calculated and summed up (luckily electro-magnetism is linear). each Particle moves accordingly (using a simple estimation approach to solve the differential movement equations) save the Particle positions repeat This seems a good approach but, for instance, it is hard to take into account symmetries that might be present (such as the magnetic field of each Quadrupole) and is this thus suboptimal. To take into account such symmetries as that of the Quadrupole field, it would be much easier to (also) make space discrete and somehow store form of the Quadrupole field somewhere. (Since 2532 or so Quadrupoles are stored this should lead to a massive gain of performance, not having to recalculate each Quadrupole field) So, are there any design patterns? Is the World-approach feasible or is it old-fashioned, bad programming? What about symmetry, how is that generally taken into acount?

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  • Log into AD account through Command Line

    - by CranialPain
    Our SBS2003 server likes to lose connection every so often. This appears to 'kick' everyone out, so that no-one can access the server or its shared folders without a log off log in. It usually brings up an error message stating that Windows 7 (on the client machines) cannot find the server, even though its ping-able. Is there a way to login through the command line so I can just write a batch file and have the users double-click it and enter their credentials instead of closing down programs and logging out/in over and over?

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  • Making a class pseudo-immutable by setting a flag

    - by scott_fakename
    I have a java project that involves building some pretty complex objects. There are quite a lot (dozens) of different ones and some of them have a HUGE number of parameters. They also need to be immutable. So I was thinking the builder pattern would work, but it ends up require a lot of boilerplate. Another potential solution I thought of was to make a mutable class, but give it a "frozen" flag, a-la ruby. Here is a simple example: public class EqualRule extends Rule { private boolean frozen; private int target; public EqualRule() { frozen = false; } public void setTarget(int i) { if (frozen) throw new IllegalStateException( "Can't change frozen rule."); target = i; } public int getTarget() { return target; } public void freeze() { frozen = true; } @Override public boolean checkRule(int i) { return (target == i); } } and "Rule" is just an abstract class that has an abstract "checkRule" method. This cuts way down on the number of objects I need to write, while also giving me an object that becomes immutable for all intents and purposes. This kind of act like the object was its own Builder... But not quite. I'm not too excited, however, about having an immutable being disguised as a bean however. So I had two questions: 1. Before I go too far down this path, are there any huge problems that anyone sees right off the bat? For what it's worth, it is planned that this behavior will be well documented... 2. If so, is there a better solution? Thanks

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  • Language bar switched input types on me.

    - by Elijah
    I learned Japanese, but I'm not native to Japan, so I never had a Japanese keyboard. I used to use the language bar to go back and forth between English and Japanese, simply typing the words in romaji and having windows convert it into either hiragana, katakana and sometimes Kanji. Suddenly, my input type changes. I am no longer able to simply type in English, it changed my keyboard into a native Japanese keyboard, and what's worse it doesn't even allow me to write in hiragana, which I would need way more than katakana. Can anyone tell me how to restore it to the old setting where I simply chose what the output dialect would be, and typed the words phonetically in english and have it translate the sounds for me into japanese characters?

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  • Install Windows XP using USB

    - by AmanBe
    How to install windows xp from usb ? I have the iso image. My cdrom is not working. I read up something on internet about this issue but all the articles are just way too complex and big + they are all different so don't know which one to try. I want to know if someone has tried something like this and to tell me what's the best and easiest way, like some tool that will automatically write the iso file onto the flash drive and make it bootable or smth. Thank you in advance.

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