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  • Temenos WealthManager: performance benchmark on Exadata

    - by Javier Puerta
    Temenos WealthManager is at work in financial institutions of all sizes. No matter the size, each of Temenos’ customers has one requirement in common: a need for fast technology. This led Temenos to conduct a performance benchmark, running its WealthManager platform on Oracle Exadata Database Machine. During the study, Temenos executed high-intensity financial engines two- to three-times faster than its previous internal benchmarks and/or largest customer throughput. The company also demonstrated greater than two-times the average improvement in response times for six-times the number of users and data volumes. Further, Temenos secured a two-times gain in service-level agreements for batch and user-oriented workloads via dedicated or parallelized processing windows. Last year Temenos also communicated the availability of its T24 core banking system and how the benchmark run demonstrated the ability of Oracle’s Exadata platform to comfortably support the highest banking volumes for T24. Read full story here  

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  • Build automation: Is it usual to use QMake for non-Qt projects?

    - by Raphael
    So, I'm planning to write a C++ library and I want it to be cross-platform, and as this library won't deal with UI and I want it to have as little dependencies as possible, I won't be using Qt (actually Qt won't really help me to achieve what I want, all I plan on using is STL and Boost). Now when it comes to build a cross-platform project, I really like QMake as it's extremely easy to use and I have experience with it. I also heard good things about CMake, though I really doubt it's as easy to use as QMake. Anyway, here is my question: Should I stick with build automation tool that I know or is QMake just out of context for a non-Qt project? Should I take this as an opportunity to learn CMake? Or is there a better alternative to these two?

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  • How to organize my 1000s of PDF?

    - by mmb
    I have a huge collection of PDF. Mostly it consists of research papers, of self-created documents but also of scanned documents. Right now I drop them all in one folder and give them precise names with tags in the filename. But even that gets impractical, so I am looking for a PDF library management application. I am thinking of something like Yep for Mac, with the following features: PDF cover browsing (with large preview, larger than Nautilus allows) tagging of PDF (data should be readable cross-platform) possibility to share across network (thus rather flat files than database) if possible: cross-platform Mendeley seemed to be a good choice, but I am not only having academic papers and don't want to fill it all metadata that is required there. The only alternative I could find thus far is Shoka, but the features are limited and developments seems to have stopped already.

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  • Native mobile app development - how do I structure my user stories?

    - by richsage
    I'm about to start on a project which will involve developing prototype native mobile apps (iOS and Android initially) as well as a web-based admin interface and an API for these apps to communicate with. We've got a list of stories already drafted up, however a lot of them are in the format: As a mobile user I want to be able to view a login screen so that I can sign into the app If this were targeted for a single platform, I wouldn't see a problem. However, since we're targeting multiple platforms, I'm not sure whether these should now be duplicated eg "As an Android user" or similar. This seems like duplication, but it's work that will need to be completed separately for each platform. This is the first mobile project we've gone native on - previously it was Phonegap and we lumped all stories in under "As a mobile user". Since essentially this was a web-based app wrapped in native code, this didn't present too much of an issue, but I'm conscious that wholly-native apps are a different ballgame!

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  • Building Enterprise Smartphone App &ndash; Part 3: Key Concerns

    - by Tim Murphy
    This is part 3 in a series of posts based on a talk I gave recently at the Chicago Information Technology Architects Group.  Feel free to leave feedback. Keys Concerns Of Smartphones In The Enterprise These are the factors that you need to be aware of and address in order to build successful enterprise smartphone applications.  Most of them have nothing to do with the application itself as you will see here. Managing Devices Managing devices is a factor that is going to effect how much your company will have to spend outside of developing the applications.  How will you track the devices within the corporation?  How often will you have to replace phones and as a consequence have to upgrade your applications to support new phones?  The devices can represent a significant investment of capital.  If these questions are not addressed you will find a number of hidden costs throughout the life of your solution. Purchase or BYOD We have seen the trend of Bring Your Own Device (BYOD) lately within the enterprise.  How many meetings have you been in where someone is on their personal iPad, iPhone, Android phone or Windows Phone?  The issue is if you can afford to support everyone's choice in device? That is a lot to take on even if you only support the current release of each platform. Do you go with the most popular device or do you pick a platform that best matches your current ecosystem and distribute company owned devices?  There is no easy answer here, but you should be able give some dollar value to both hardware and development costs related to platform coverage. Asset Tracking/Insurance Smartphones are devices that are easier to lose or have stolen than laptops and desktops. Not only do you have your normal asset management concerns but also assignment of financial responsibility. You also will need to insure them against damage and theft and add legal documents that spell out the responsibilities of the employees that use these devices. Personal vs. Corporate Data What happens when you terminate an employee?  How do you recover the device?  What happens when they have put personal data on the device?  These are all situation that can cause possible loss of corporate intellectual property or legal repercussions of reclaiming a device with personal data on it.  Policies need to be put in place that protect the company from being exposed to type of loss.  This can mean significant legal and procedural cost that you need to consider. Coming Up In the last installment of this series I will cover application development considerations. del.icio.us Tags: Smartphones,Enterprise Smartphone Apps,Architecture

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  • Tell the CDI 2 Expert Group What You Think!

    - by reza_rahman
    Since it's introduction in Java EE 6, CDI has become a key API for the platform. CDI 1.1 was a relatively minor release included in Java EE 7 as was CDI 1.2 (to be included in GlassFish 4.0.1). We have much higher expectations from CDI 2 (projected to be included in Java EE 8) under the new leadership of Antoine Sabot-Durand. Much like we conducted the Java EE 8 survey to solidify future direction for the platform, CDI 2 is now undergoing the same effort. Towards this goal the CDI 2 leadership is now soliciting feedback on some very specific items via an open survey. Topics include the likes of Java SE bootstrap, asynchronous processing, modularity, EJB-style @Startup and @Asynchronous in CDI, configuration and CDI Lite. You can of course also provide free-form input on anything that's not on the survey. Take the survey now on the CDI specification site and help shape the future of CDI 2 and Java EE 8!

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  • Oracle RightNow Cloud Service Roadmap - Live Webcast, Nov 13, 6pm CET

    - by Richard Lefebvre
    Did you miss out on Oracle OpenWorld this year? Then make sure you don’t miss out on this Webinar.  The Oracle RightNow development team shares the latest innovations and integrations, including future roadmap, for the Oracle RightNow Service Cloud platform.  Find out how these innovations will help you deliver exceptional customer service to your customers.Join our live Webcast on Wednesday, November 13, 2013, 09:00 a.m. PT / 12:00 p.m. ET (18:00 p.m. CET) to get up to speed with the latest updates and future capabilities, and learn how you can: Provide a more engaging Web experience Increase the effectiveness of assisted service Deliver the right answer at the right time - all the time Agenda Topics How RightNow fits into Oracle's vision for Oracle Service The latest updates to the Oracle RightNow Cloud Service platform Oracle's key investment areas and roadmap for Oracle RightNow Cloud Service Don’t miss this chance to learn how you can delight your customers while improving cost and efficiency.Register Now

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  • What would you choose for your project between .NET and Java at this point in time ?

    - by Basic
    You are just starting a new project and you have these two technologies to choose from, Java and .NET. The project you are working doesn't involve having features that would make it easy to choose between the two technologies (e.g. .NET has this that I need and Java does not) and both of them should work just fine for you (though you only need one of course). Take into account: Performance Tools available (even 3rd party tools) Cross platform compatibility Libraries (especially 3rd party libraries) Cost (Oracle seems to try and monetize Java) Development process (Easiest/Fastest) Also keep in mind that Linux is not your main platform but you would like to port your project to Linux/MacOs as well. You should definitely keep in mind the trouble that has been revolving around Oracle and the Java community and the limitations of Mono and Java as well. It would be much appreciated if people with experience in both can give an overview and their own subjective view about which they would choose and why.

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  • Inversion of control in Unity?

    - by user3206275
    I am semi-experienced .NET developer who has just began working with Unity. I am trying to decide on how to make IoC work in Unity 4.X ( I have not yet tested anything), and I wonder what are the good ways of achieving it. This post and its answers states that Ninject won't work with Unity, however it is old. Is it still true? If yes, what are other means of achieving IoC in Unity ? Edit 1 : I am targeting mainly Windows platform. So I don't need platform interoperability, I just need it to work.

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  • Why I am getting following error when trying to start SDK manager?

    - by rishiag
    I have a 64 bit- 20 GB Ubuntu partition which has very less usable space. So I have put Eclipse in my Ubuntu and downloaded sdks to a folder in my another partition. So when I try to start sdk manager, I am getting the following error in my console: Unexpected exception 'Cannot run program "/media/Data/android-sdks/platform-tools/adb": error=13, Permission denied' while attempting to get adb version from '/media/Data/android-sdks/platform-tools/adb' I have run chmod recursively on android-sdks directory. If I change the address for sdks to Ubuntu partition, sdk manager starts successfully. Is there anything I can do other than increasing the partition size? Thanks

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  • Down to the Wire - Yet More Solaris Things to See at OpenWorld (and JavaOne!)

    - by Larry Wake
    San Francisco is bracing for the annual invasion. The airport's jammed, the tweets are flying, and the numbers are crazy: more than 50,000 attendees and 2,500+ sessions, taking over Moscone Convention Center, two streets, Union Square, and seemingly every hotel in town (98,000 hotel room nights). So yeah, it's busy. And it's not just OpenWorld--we've also got JavaOne, MySQL Connect, and four other sub-events going on as well. Speaking of JavaOne, you can find Solaris-related activity there, too -- I've highlighted one hands-on lab below. Here's a last pre-event roundup of activities for consideration; enjoy the show(s)! (Remember, Schedule Builder is your friend; use it with the session numbers below to register.) Monday, October 1st: 3:15 PM - General Session: Accelerate Your Business with the Oracle Hardware Advantage(GEN9691, Moscone North Hall D) John Fowler, head of Oracle's Systems organization, will talk about Oracle hardware technology and how it's co-engineered with other key technologies, including Oracle Solaris. Tuesday, October 2nd: 10:15 AM - Building an IaaS Platform with SPARC, Oracle Solaris 11, and Oracle VM Server for SPARC(CON4431, Moscone South 270)Get the birds-eye lowdown (whatever that means) on how U.S. Cellular  built its Infrastructure as a Service (IaaS) cloud delivery platform with Oracle’s SPARC T4 servers, Oracle Solaris 11, Oracle Solaris Cluster 4, and Oracle VM Server for SPARC. The session covers the high-level design, business case made, implementation details, and lessons learned. 11:45 AM - Oracle Solaris 11 Panel: Insights and Directions from Oracle Solaris Core Engineering(CON8790, Moscone South 252) This has been one of the livelier Solaris-related sessions in years past (and I'm not saying that just because I get to moderate it this year). A panel of core engineers responsible for a wide range of key Solaris technologies will talk about some of the interesting work they've been doing -- but mostly we keep time open for the panel to take questions from attendees, because that's the fun part. Wednesday, October 3rd: 10:00 AM - Tracing Your Java Application Tuning on Oracle Solaris with DTrace(HOL10214, Hilton San Francisco, Franciscan A/B/C/D) This JavaOne hands-on lab will show how to use the DTrace framework to dynamically trace your Java applications on Oracle Solaris and uncover new tuning opportunities. Thursday, October 4th: 12:45 PM - Oracle Solaris 11: Optimized for Oracle Database, Oracle WebLogic Server, and Java(CON8800, Moscone South 252) Explore how Oracle Solaris 11 has been built to be the best platform for the cloud and enterprise applications, with built-in optimizations to improve performance and deliver unique functionality with Oracle Database, Oracle WebLogic Server, and Java.

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  • The model item passed into the dictionary is of type ‘mvc.Models.ModelA’ but this dictionary require

    - by Malcolm Frexner
    I have this annoying mistake in some of my builds. There is no error in the project, because if I build again, then the problem disappears. The message only appears, when the site is deployed to a Windows 2008 Server. I first thought that it might be an issue with temporary files, but thats not the case. I deployed the build to a different web and the error still appears. The error appears on random actions of the site. Most of the time builds are ok, but each 3rd or 4th build produces runtime errors. I build using a WebdeploymentProject in release mode. Views are precompiled. It's not http://stackoverflow.com/questions/178194/in-asp-net-mvc-i-encounter-an-incorrect-type-error-when-rendering-a-page-with-the, because views have totally different names. How I can debug this problem or how I can get help for this? Here is my WebDeploymentProject <!-- Microsoft Visual Studio 2008 Web Deployment Project http://go.microsoft.com/fwlink/?LinkID=104956 --> <Project ToolsVersion="3.5" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003"> <PropertyGroup> <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration> <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform> <ProductVersion>9.0.21022</ProductVersion> <SchemaVersion>2.0</SchemaVersion> <ProjectGuid>{E5E14CEB-0BCD-4203-9A5A-34ABA9C717EA}</ProjectGuid> <SourceWebPhysicalPath>..\B2CWeb</SourceWebPhysicalPath> <SourceWebProject>{3E632DB6-6DB3-4BD0-8CCA-12DE67165B48}|B2CWeb\B2CWeb.csproj</SourceWebProject> <SourceWebVirtualPath>/B2CWeb.csproj</SourceWebVirtualPath> <TargetFrameworkVersion>v3.5</TargetFrameworkVersion> </PropertyGroup> <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' "> <DebugSymbols>true</DebugSymbols> <OutputPath>.\Debug</OutputPath> <EnableUpdateable>false</EnableUpdateable> <UseMerge>true</UseMerge> <SingleAssemblyName>B2CWeb_Build</SingleAssemblyName> </PropertyGroup> <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' "> <DebugSymbols>false</DebugSymbols> <OutputPath>..\B2CWeb_Deploy\</OutputPath> <EnableUpdateable>false</EnableUpdateable> <UseMerge>true</UseMerge> <SingleAssemblyName>B2C_Web</SingleAssemblyName> <ContentAssemblyName> </ContentAssemblyName> <DeleteAppCodeCompiledFiles>false</DeleteAppCodeCompiledFiles> </PropertyGroup> <ItemGroup> </ItemGroup> <Import Project="$(MSBuildExtensionsPath)\Microsoft\WebDeployment\v9.0\Microsoft.WebDeployment.targets" /> <!-- To modify your build process, add your task inside one of the targets below and uncomment it. Other similar extension points exist, see Microsoft.WebDeployment.targets. <Target Name="BeforeBuild"> </Target> <Target Name="BeforeMerge"> </Target> <Target Name="AfterMerge"> </Target> <Target Name="AfterBuild"> </Target> --> </Project>

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  • In Ruby, how to I read memory values from an external process?

    - by grg-n-sox
    So all I simply want to do is make a Ruby program that reads some values from known memory address in another process's virtual memory. Through my research and basic knowledge of hex editing a running process's x86 assembly in memory, I have found the base address and offsets for the values in memory I want. I do not want to change them; I just want to read them. I asked a developer of a memory editor how to approach this abstract of language and assuming a Windows platform. He told me the Win32API calls for OpenProcess, CreateProcess, ReadProcessMemory, and WriteProcessMemory were the way to go using either C or C++. I think that the way to go would be just using the Win32API class and mapping two instances of it; One for either OpenProcess or CreateProcess, depending on if the user already has th process running or not, and another instance will be mapped to ReadProcessMemory. I probably still need to find the function for getting the list of running processes so I know which running process is the one I want if it is running already. This would take some work to put all together, but I am figuring it wouldn't be too bad to code up. It is just a new area of programming for me since I have never worked this low level from a high level language (well, higher level than C anyways). I am just wondering of the ways to approach this. I could just use a bunch or Win32API calls, but that means having to deal with a bunch of string and array pack and unpacking that is system dependant I want to eventually make this work cross-platform since the process I am reading from is produced from an executable that has multiple platform builds, (I know the memory address changes from system to system. The idea is to have a flat file that contains all memory mappings so the Ruby program can just match the current platform environment to the matching memory mapping.) but from the looks of things I'll just have to make a class that wraps whatever is the current platform's system shared library memory related function calls. For all I know, there could already exist a Ruby gem that takes care of all of this for me that I am just not finding. I could also possibly try editing the executables for each build to make it so whenever the memory values I want to read from are written to by the process, it also writes a copy of the new value to a space in shared memory that I somehow have Ruby make an instance of a class that is a pointer under the hood to that shared memory address and somehow signal to the Ruby program that the value was updated and should be reloaded. Basically a interrupt based system would be nice, but since the purpose of reading these values is just to send to a scoreboard broadcasted from a central server, I could just stick to a polling based system that sends updates at fixed time intervals. I also could just abandon Ruby altogether and go for C or C++ but I do not know those nearly as well. I actually know more x86 than C++ and I only know C as far as system independent ANSI C and have never dealt with shared system libraries before. So is there a gem or lesser known module available that has already done this? If not, then any additional information as to how to accomplish this would be nice. I guess, long story short, how do I do all this? Thanks in advance, Grg PS: Also a confirmation that those Win32API calls should be aimed at the kernel32.dll library would be nice.

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  • If 'Architect' is a dirty word - what's the alternative; when not everyone can actually design a goo

    - by Andras Zoltan
    Now - I'm a developer first and foremost; but whenever I sit down to work on a big project with lots of interlinking components and areas, I will forward-plan my interfaces, base classes etc as best I can - putting on my Architect hat. For a few weeks I've been doing this for a huge project - designing whole swathes of interfaces etc for a business-wide platform that we're developing. The basic structure is a couple of big projects that consists of service and data interfaces, with some basic implementations of all of these. On their own, these assemblies are useless though, as they are simply intended intended as a scaffold on which to build a business-specific implementation (we have a lot of businesses). Therefore, the design of the core platform is absolutely crucial, since consumers of the system are not intended to know which implementation they are actually using. In the past it's not worked so well, but after a few proof-of-concepts and R&D projects this new platform is now growing nicely and is already proving itself. Then somebody else gets involved in the project - he's a TDD man who sees code-level architecture as an irrelevance and is definitely from the camp that 'architect' is a dirty word - I should add that our working relationship is very good despite this :) He's open about the fact that he can't architect in advance and obviously TDD really helps him because it allows him to evolve his systems over time. That I get, and totally understand; but it means that his coding style, basically, doesn't seem to be able to honour the architecture that I've been putting in place. Now don't get me wrong - he's an awesome coder; but the other day he needed to extend one of his components (an implementation of a core interface) to bring in an extra implementation-specific dependency; and in doing so he extended the core interface as well as his implementation (he uses ReSharper), thus breaking the independence of the whole interface. When I pointed out his error to him, he was dismayed. Being test-first, all that mattered to him was that he'd made his tests pass, and just said 'well, I need that dependency, so can't we put it in?'. Of course we could put it in, but I was frustrated that he couldn't see that refactoring the generic interface to incorporate an implementation-specific feature was just wrong! But it is all very Charlie Brown to him (you know the sound the adults make when they're talking to the children) - as far as he's concerned we don't need to worry about it because we can always refactor. The problem is, the culture of test-write-refactor is all very well and good - but not when you're dealing with a platform that is going to be shared out among so many projects that you could never get them all in one place to make the refactorings work. In my opinion, sometimes you actually have to think about what you're doing, and not just let nature take its course. Am I simply fulfilling the role of Architect as a dirty word here? I believe that architecture is important and should be thought about before code gets written; unless it's a particularly small project. But when you're working in a team of people who don't think that way, or even can't think that way how can you actually get this across? Is it a case of simply making the architecture off-limits to changes by other people? I don't want to start having bloody committees just to be able to grow the system; but equally I don't want to be the only one responsible for it all. Do you think the architect role is a waste of time? Is it at odds with TDD and other practises? Can this mix of different practises be made to work, or should I just be a lot less precious (and in so doing allow a generic platform become useless!)? Or do I just lay down the law? Any ideas/experiences/views gratefully received.

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  • Password Manager that allows syncing accross platforms

    - by lexu
    I use OS X, Linux, Solaris and windows for work and from home. There are good tools that allow me to manage the many logins/passwords required platform independently. But mostly they expect me to carry a thumb-drive around or require direct access to a central location (a sky drive in the cloud). The thumb-drive is too easily lost (= synchronized backup needed), the central location not always reachable/ mountable. Besides company policy rightly prevents this often. Is there a tool that allows me to add passwords locally and then syncs it's DB with the "mother-ship" later. Or is there another approach that you use, that solves my problem? EDIT My question is more about "synchronize" than cross platform. I've evaluated (=read feature list) some good cross platform tools, but need one that does the synchronizing for me. By synchronize I mean "merge two versions" not "replace (hopefully) old file with new." I'm not sure I'm always disciplined/awake enough to prevent data loss. UPDATE Lifehacker just posted that AgileSolutions now have a beta version of 1Password for Windows.

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  • The long road to bug-free software

    - by Tony Davis
    The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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  • The long road to bug-free software

    - by Tony Davis
    The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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  • How to catch segmentation fault in Linux?

    - by Alex Farber
    I need to catch segmentation fault in third party library cleanup operations. This happens sometimes just before my program exits, and I cannot fix the real reason of this. In Windows programming I could do this with __try - __catch. Is there cross-platform or platform-specific way to do the same? I need this in Linux, gcc.

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  • NO such file or directory for the files -----stdarg.h and float.h ?

    - by balraj
    HI all I am using some files on .mm extension in the xcode project for compiling these files we have added the LLVM-GCC 4.2 in the build setting after adding this compiler this showing the error /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator3.1.sdk/usr/include/stdarg.h:4:25: error: stdarg.h: No such file or directory /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator3.1.sdk/usr/include/float.h:8:24: error: float.h: No such file or directory i have no idea how to remove this error any help to remove this error. thanks Balraj

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