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  • Simplifying the process of compiling and running objective-c apps in GNUstep

    - by Matthew
    I just installed GNUstep (following this post: http://www.jaysonjc.com/programming/objective-c-programming-in-windows-gnustep-projectcenter.html) It says to run this code: gcc -o helloworld helloworld.m -I /GNUstep/System/Library/Headers -L /GNUstep/System/Library/Libraries -lobjc -lgnustep-base -fconstant-string-class=NSConstantString every time I want to compile. It works just fine for me. However as I'm learning and will be compiling/running apps way often (making little changes and trying again), I'd like a simpler way to do this. Is there an easier way to compile and then run the app? Or am I just being lazy?

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  • Chess as a team building exercise for software developers

    - by maple_shaft
    The last place I worked wasn't a particularly great place and there were more than a few nights where we were working late into the evening trying to meet our sprints. The team while stressed out got pretty close and people started bringing in little mind teasers and puzzles, just something we would all play around with and try to solve while a build/deploy was running for the test environment, or while we were waiting for the integration test run to finish. Eventually it turned into people bringing chess boards in and setting them at their desks. We would play by email sending each other moves in chess notation, but at a very casual pace, with games lasting sometimes two or three days. Management tolerated this when we were putting in overtime, but as things were being managed better and people weren't working much more than 40/wk, they started cracking down on this and told us that we weren't allowed to have chess boards at our desks, although they were okay with the puzzle games. What are the pros and cons in your opinion of allowing chess during software development lull time?

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  • How can I get job in company when I unfamiliar with technology [closed]

    - by Michael Z
    Sorry if I have chosen wrong stackexchange site for this question. Point me in correct place if any... How can I get job in company that have some unfamiliar technology for me in they Job Requirements list? In other words. How can I get job on Lucene if I have not any experience on Lucene, but for getting experience in Lucene I need to be involved in company that needs developers with Lucene technology experience? It is closed disk!

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  • What is your favourite/ideal development environment?

    - by Nico Huysamen
    If you could describe your ideal development environment, what would it be? There are numerous things to take into consideration, including but not limited to: Hardware Software (Operating System of Choice, Paid vs. Free Software, ...) Physical Environment (lighting, open-plan, location, ...) An endless supply of coffee... ... In other words, if you could tell your company what they could do to make your development experience there better, what would it be?

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  • Windows Azure Emulators On Your Desktop

    - by BuckWoody
    Many people feel they have to set up a full Azure subscription online to try out and develop on Windows Azure. But you don’t have to do that right away. In fact, you can download the Windows Azure Compute Emulator – a “cloud development environment” – right on your desktop. No, it’s not for production use, and no, you won’t have other people using your system as a cloud provider, and yes, there are some differences with Production Windows Azure, but you’ll be able code, run, test, diagnose, watch, change and configure code without having any connection to the Internet at all. The best thing about this approach is that when you are ready to deploy the code you’ve been testing, a few clicks deploys it to your subscription when you make one.   So what deep-magic does it take to run such a thing right on your laptop or even a Virtual PC? Well, it’s actually not all that difficult. You simply download and install the Windows Azure SDK (you can even get a free version of Visual Studio for it to run on – you’re welcome) from here: http://msdn.microsoft.com/en-us/windowsazure/cc974146.aspx   This SDK will also install the Windows Azure Compute Emulator and the Windows Azure Storage Emulator – and then you’re all set. Right-click the icon for Visual Studio and select “Run as Administrator”:    Now open a new “Cloud” type of project:   Add your Web and Worker Roles that you want to code:   And when you’re done with your design, press F5 to start the desktop version of Azure:   Want to learn more about what’s happening underneath? Right-click the tray icon with the Azure logo, and select the two emulators to see what they are doing:          In the configuration files, you’ll see a “Use Development Storage” setting. You can call the BLOB, Table or Queue storage and it will all run on your desktop. When you’re ready to deploy everything to Windows Azure, you simply change the configuration settings and add the storage keys and so on that you need.   Want to learn more about all this?   Overview of the Windows Azure Compute Emulator: http://msdn.microsoft.com/en-us/library/gg432968.aspx Overview of the Windows Azure Storage Emulator: http://msdn.microsoft.com/en-us/library/gg432983.aspx January 2011 Training Kit: http://www.microsoft.com/downloads/en/details.aspx?FamilyID=413E88F8-5966-4A83-B309-53B7B77EDF78&displaylang=en      

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  • What stressors do programmers encounter on the job, and how do you deal with them? [closed]

    - by Matthew Rodatus
    Learning to manage stress is vital to staying healthy while working at any job. A necessary subtask is learning to recognize and limit the sources of stress. But, in the midst of the daily grind, it can be difficult to recognize sources of stress (especially for an intense, focused persona such as a programmer). What types of stressors should programmers look out for, and how can they be managed?

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  • How to use multiple monitors effectivelly

    - by maaartinus
    I'm currently using a single monitor, since I see no value in something like this mentioned in this answer. It may be a good exercise for my neck, but besides of this I see no use therein at all. This amounts to 5760x1200 pixels, which is nearly 7M pixels, just fantastic, except for me not being a cyklop-han. The ratio of 24:5 is IMHO too bad for this to be usable. I don't even think that two 16:10 monitors side by side is a good idea. I never tried so I may be completely wrong, but I suppose that the 4:3 ratio would be much better for this. Or even 1:1, but no such thing is available (with some exceptions, either very expensive or very low resolution). Does anybody use two monitors arranged vertically (resulting in 16:20)? or two pivoted monitors side by side (resulting in 20:16)? or another such variant?

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  • What kind of screen has the best image quality for reading/programming?

    - by EpsilonVector
    I'm thinking about buying a new laptop, and while I bought my original one oblivious to the fact that there could be different quality screens out there, after seeing the screen on my sister's netbook I realized that I might have to be cautious with my next purchase. Granted, I did not confirm that the reason my sister's screen looks the way it does is due to the screen itself and not color scheme/graphics card, but I know very little about the different screen technologies and how they differ in image quality and therefore can't really tell if wondering about it even makes sense or not. So what I'm asking is: should I be worried about screen quality? And if so, what technologies should I be looking for? How do they differ and which are the best ones? What are the different elements that determine the quality of a screen and which stats should I go for in each element? For the record, I'm not interested in opinions about screen size, but picture quality for lots of reading/coding.

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  • Recommendations for adjustable sit-stand workstations?

    - by Chris Phillips
    Recently, I've been feeling the discomfort of sitting at my desk all day long. I'm fairly active, stretch, and take regular breaks, but some days it's still pretty uncomfortable to sit all day long, whether in a nice chair or on an exercise ball. I would really like able to stand at my computer for part of the day. My current setup is a large desk with two 26" lcds and a 17" laptop. I don't mind if the laptop isn't adjustable, as I don't use it as regularly as the monitors. I would like to be able to fairly easily switch from a sitting position to a standing position and back again as necessary. I've been looking into adjustable height desks and stands and found that they tend to be either really expensive, or don't quite meet my needs. (For example, the Ergotron WorkFit-S Dual LCD workstation looks like the ideal feature set at a reasonable price, but won't fit with my monitors.) Any suggestions or thoughts? Update: fixed a typo. Thanks @RDL!

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  • Paypal PDT and IPN , how does it work?

    - by slow diver
    PDT Payment Data Transfer is getting the transaction data of the purchase that was made on paypal site and you want to fetch that on your own site and display to the user. Also you may want to store it in your database for archive and tracking purposes. But I cannot exactly follow the documentation here What I am not getting is Once you have activated PDT, every time a buyer makes a website payment and is redirected to your return URL, a transaction token will be passed along as a "GET" variable to this return URL. In order to properly use PDT and display transaction details to your customer, you should fetch the transaction token, variable name "tx", and retreive transaction details from PayPal by constructing an HTTP POST to PayPal. Your POST should be sent to https://www.paypal.com/cgi-bin/webscr. You must post the transaction token using the variable "tx" and the value of the transaction token previously received (e.g. "tx=transaction_token"), and the special identity token using the variable at and the value of your PDT identity token (e.g. "at=identity_token"). You will also need to append a variable named "cmd" with the value "_notify-synch", for example "cmd=_notify-synch", to the POST string. IPN I have setup Instant Payment Notification through setting according to this documentation. This is basically logging into your paypal account and enable IPN while specifying a url where the notification will be sent. This is used to complete an order so that the product can be shipped. What I did is setup a PHP page. I have created a table and whenever that page is called (or hit), it registers an entry in the table so I know a notification came from Paypal. But it does not work either. What am I really doing wrong? The first thing I want to trouble shoot though is when the buyer pays the amount, he is automatically redirected to my site. I have enabled this but automatic redirection just does not work. Instead he is shown the url as an option after payment confirmation is shown. Can someone guide my how the PDT process goes? Where do I make the request for PDT, is it along the very first request (Buy Now button) or it is sent later? Addition I found some good sampling code of how everything should work but it still does not work. I use this code http://officetrio.com/modules/free-php-paypal-ipn-script.php for IPN. I am using this for PDT. This one uses SSL, I changed SSL to regular HTTP (copied paypal version), still does not work. http://ykyuen.wordpress.com/2010/02/17/paypal-payment-data-transfer-sample-code/

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  • Windows Azure Emulators On Your Desktop

    - by BuckWoody
    Many people feel they have to set up a full Azure subscription online to try out and develop on Windows Azure. But you don’t have to do that right away. In fact, you can download the Windows Azure Compute Emulator – a “cloud development environment” – right on your desktop. No, it’s not for production use, and no, you won’t have other people using your system as a cloud provider, and yes, there are some differences with Production Windows Azure, but you’ll be able code, run, test, diagnose, watch, change and configure code without having any connection to the Internet at all. The best thing about this approach is that when you are ready to deploy the code you’ve been testing, a few clicks deploys it to your subscription when you make one.   So what deep-magic does it take to run such a thing right on your laptop or even a Virtual PC? Well, it’s actually not all that difficult. You simply download and install the Windows Azure SDK (you can even get a free version of Visual Studio for it to run on – you’re welcome) from here: http://msdn.microsoft.com/en-us/windowsazure/cc974146.aspx   This SDK will also install the Windows Azure Compute Emulator and the Windows Azure Storage Emulator – and then you’re all set. Right-click the icon for Visual Studio and select “Run as Administrator”:    Now open a new “Cloud” type of project:   Add your Web and Worker Roles that you want to code:   And when you’re done with your design, press F5 to start the desktop version of Azure:   Want to learn more about what’s happening underneath? Right-click the tray icon with the Azure logo, and select the two emulators to see what they are doing:          In the configuration files, you’ll see a “Use Development Storage” setting. You can call the BLOB, Table or Queue storage and it will all run on your desktop. When you’re ready to deploy everything to Windows Azure, you simply change the configuration settings and add the storage keys and so on that you need.   Want to learn more about all this?   Overview of the Windows Azure Compute Emulator: http://msdn.microsoft.com/en-us/library/gg432968.aspx Overview of the Windows Azure Storage Emulator: http://msdn.microsoft.com/en-us/library/gg432983.aspx January 2011 Training Kit: http://www.microsoft.com/downloads/en/details.aspx?FamilyID=413E88F8-5966-4A83-B309-53B7B77EDF78&displaylang=en      

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  • How can I create a solid business case for upgrading our programmers to 256 GB SSD and 16 GB of RAM?

    - by Alex. S.
    We have an environment based on Microsoft stack (VS2010, SQL Server, etc), and I firmly believe that we could improve productivity a little bit, having more RAM and a faster secondary SSD. What data do you advice to gather so I can solidify my request in such a way the advantages can be unbiasedly demonstrated? Currently we have only 6GB of RAM and slower HD drives, and at home I have a 128 GB SSD in my desktop and 16 GB of RAM (I also think is the max amount of memory supported by our workstations, if we could go bigger then better), so I can feel the difference and it's real. I also want to add that we are in an industry with plenty of money, so the issue actually is how to get a budget approval from management and spend it wisely to increase productivity.

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  • What are some good questions (and good/bad answers) to ask at an interview to gauge the competency of the company/team?

    - by Wayne M
    I'm already familiar with the Joel Test, but it's been my experience that some of the questions there have the answers "massaged" to make the company seem better than it is. I've had several jobs in the past that, for instance, claimed they had a QA process and did unit testing, and what they really meant is "The programmers test the app, and test with the debugger and via trial-and-error."; they said they used SVN but they just lumped everything into one giant repository and had no concept of branching/merging or anything more complicated than updating and committing; said they can build in one step and what they really mean is it's "one step" to copy dozens of files by hand from the programmer's PC to the live server. How do you go about properly gauging a company's environment to make sure that it's a well-evolved company and not stuck on doing things a certain way because they've done it for years and they're ignorant of change? You can almost never ask to see their source code, so you're stuck trying to figure out if the interviewer's answer is accurate or BS to make the company seem good. Besides the Joel Test what are some other good questions to get the proper feel for a company, and more importantly what are some good and bad answers that could indicate a good or bad company? I mean something like (take at face value, please, it's all I could think of at short notice): Question: How does the software team apply the SOLID principles and Inversion of Control to their code? Good Answer: We adhere to SOLID wherever possible; we use TDD so it kind of forces us to write abstract, testable code. We use Ninject for our IoC container because it's fairly easy to configure - it was that or StructureMap but I find Ninject a bit more intuitive, and who doesn't like ninjas? You're not a pirate, are you? Bad Answer: Our code is pretty secure, yeah. And what's this Inversion of Control thing? I've never heard of it before. You see what I did there. The "good" answer uses facts to back it up and has a bit of "in crowd" humor; the bad answer shows complete ignorance of the question - not necessarily a bad thing if you are interviewing for a manger/director position, but a terrible answer and a huge red flag if you're interviewing as a developer and talking to a senior developer or manager! My biggest problem at the moment is being able to take a generic response and gauge whether it's the good or bad answer; more often than not it's the bad kind and I find myself frustrated almost from day one at the new job. I suppose I could name drop if I ask about specific things (e.g. "Do you write unit tests?" and if the answer is yes, ask if they use NUnit, MbUnit or something else; if they mention data access ask if they use a clean ORM like NHibernate or something more coupled like EF or Linq) but is there another way short of being resolute to actually call the interview on things (which will almost certainly result in not getting the job, but if they are skirting the question it's probably not a job I want).

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  • Eyes easily get dry and itchy [closed]

    - by Lo Wai Lun
    I have currently working as a programmer for half a year Very often, I often looking the monitors with natural contrast and brightness. Still when the weather is getting cold, my eyes feel dry and itchy. Sometimes I can see some red 'tree-roots' (capillaries) near iris. At home, i sometimes use my notebook for 13" or Galaxy Nexus Brightness are also natural contrast and brightness , a bit dim How should we take care of our eyes under this scenario?

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  • Kinect office demo ideas

    - by Tedd Hansen
    I'm thinking of placing a Kinect (connected to a PC) in the office and have something fun on it. Just a small thing people can interact with. Basically I get a depthmap (image) and a color image from the Kinect which I can analyze and do stuff with. My limited imagination came up with: Count people passing by. Measure average width of people passing by. Some ball with physics people can play with. Audible alert when someone is walking too fast. Anyone have any good ideas? :)

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  • Games at Work Part 2: Gamification and Enterprise Applications

    - by ultan o'broin
    Gamification and Enterprise Applications In part 1 of this article, we explored why people are motivated to play games so much. Now, let's think about what that means for Oracle applications user experience. (Even the coffee is gamified. Acknowledgement @noelruane. Check out the Guardian article Dublin's Frothing with Tech Fever. Game development is big business in Ireland too.) Applying game dynamics (gamification) effectively in the enterprise applications space to reflect business objectives is now a hot user experience topic. Consider, for example, how such dynamics could solve applications users’ problems such as: Becoming familiar or expert with an application or process Building loyalty, customer satisfaction, and branding relationships Collaborating effectively and populating content in the community Completing tasks or solving problems on time Encouraging teamwork to achieve goals Improving data accuracy and completeness of entry Locating and managing the correct resources or information Managing changes and exceptions Setting and reaching targets, quotas, or objectives Games’ Incentives, Motivation, and Behavior I asked Julian Orr, Senior Usability Engineer, in the Oracle Fusion Applications CRM User Experience (UX) team for his thoughts on what potential gamification might offer Oracle Fusion Applications. Julian pointed to the powerful incentives offered by games as the starting place: “The biggest potential for gamification in enterprise apps is as an intrinsic motivator. Mechanisms include fun, social interaction, teamwork, primal wiring, adrenaline, financial, closed-loop feedback, locus of control, flow state, and so on. But we need to know what works best for a given work situation.” For example, in CRM service applications, we might look at the motivations of typical service applications users (see figure 1) and then determine how we can 'gamify' these motivations with techniques to optimize the desired work behavior for the role (see figure 2). Description of Figure 1 Description of Figure 2 Involving Our Users Online game players are skilled collaborators as well as problem solvers. Erika Webb (@erikanollwebb), Oracle Fusion Applications UX Manager, has run gamification events for Oracle, including one on collaboration and gamification in Oracle online communities that involved Oracle customers and partners. Read more... However, let’s be clear: gamifying a user interface that’s poorly designed is merely putting the lipstick of gamification on the pig of work. Gamification cannot replace good design and killer content based on understanding how applications users really work and what motivates them. So, Let the Games Begin! Gamification has tremendous potential for the enterprise application user experience. The Oracle Fusion Applications UX team is innovating fast and hard in this area, researching with our users how gamification can make work more satisfying and enterprises more productive. If you’re interested in knowing more about our gamification research, sign up for more information or check out how your company can get involved through the Oracle Usability Advisory Board. Your thoughts? Find those comments.

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  • Boss solution vs Developer solution

    - by mahen23
    The problem: When we were sending newsletters to customers, there was no way to confirm if the customer already received the mail. So the boss decided to implement this idea: Boss's Idea: Each time mail was being sent, do an INSERT in a db with the title of the newsletter being sent and the email address which is receving the email address. To ensure that any email address does not receive the same email twice, do a SELECT in the table and find the title of the newsletter being sent: if (title of newsletter is found) { check to see of the email we are sending mail to is already present. if it does, do not send mail } else { send mail } MY idea: create a column called unique and mark it as UNIQUE. Each time mail was being sent, concatenate email + newsletter id and record it in the UNIQUE row. The next time we do a "mysql_affected_rows" check to see if our INSERT was successful, we send the mail, else, there is already a duplicate and no need to send it.

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  • Stuff every programmer needs while working

    - by Desai Shukla
    I've been tasked with creating a fun and relaxing environment, one thing I know that I want is ergonomic mice and keyboards, others have suggested exercise balls and bands. What is it that every programmer needs while working? What might not be necessary but would be nice to have anyway? Note: this question was asked previously, but has been recommended to be posted here. See this link for the previous responses: http://stackoverflow.com/questions/3911911/stuff-every-programmer-needs-while-working-closed

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  • How to tell your boss that his programming style is really bad?

    - by Roflcoptr
    I'm a student and in my spare time I'm working for a big enterprise as Java developer. The job is good, but the problem is, my boss is writing very strange code. I don't want to complain, but some issues are in my opinion really strange. For example: he doesn't know any booleans. All boolean conditions are Strings called "YesOrNo" and then in the condition he uses if (YesOrNo == "Yes") there are a lot of very strange characters in method names and variables like é õ ô or è all loops are infinite loops in the style of for(;;). Then at the end of the loop the condition is tested and if the conditions is fulfilled break; is called. I don't now if I should tell him that I think this isn't a good practice, since he is my boss and decides how and what to do. On the other hand some of this examples are really very weird. Any hints how to cope with? And is this only me who thinks that's bad style?

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  • What tool do you use to organise your tasks?

    - by Gearóid
    Hi, I've been a web developer for four years now and I've yet to come across a nice piece of software that allows me to manage my day to day tasks well. In theory, I should be able to just pull up a textfile and write: write test scripts check code into svn remember to go home But obviously this isnt very usable. I've tried stuff like Ta-da List but it feels quite limited. JIRA is great for bug tracking but what if I have to remember to go to the bank at 2pm. Is there anything piece of software out there that helps organise programmers? I'm really interested in hearing what you guys have to say on this one. Thanks.

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  • How to convince my boss to improve code quality?

    - by Vimvq1987
    The place I'm working for is a service provider. We have a lot of services, which are written to deal with deadline, so their code are really terrible: No coding convention, everyone codes in his own style No unit testing (which is really bad) No refactoring (which is truly worse) No automation build/deployment etc and these code are used again and again, so bad code continue to spread all over my department. I really want to set up a standard quality for our code, by requiring everyone to follow "rules": every line of code which does not follow convention will be rejected, and every function of code which does not pass unit testing will not be committed,...But I don't know how to convince my boss to allow me to do this. I'm relatively new comer, so inspiring people from my works is really hard, and I think it's easier if my boss support me to this. Thank you very much for your advices

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  • I'm a C Programmer, but I can't find a comfortable environment to work in

    - by Jesse Brands
    Hello everyone, Last time I asked a question, I was having issues dealing with Java which I had to do for a course work. I generally use C for my development work - especially personal projects - and I've grown up in what is pretty much a Linux/UNIX world. In this world, it was easy to use C, you had your C compiler (GCC is excellent in that regard) and a wealth of tools such as the command line and vi/emacs/whatever-you-got. However, that was all that I really liked about Linux/UNIX. It really fitted well with the C language; nowadays, I'm somewhat forced into Windows/Mac OS X for most of my work. C seems poorly supported on a mac for starters, there's no GUI API to use and pretty much you get forced into Obj-C. This is not a problem, I like Objective-C, but it's another language I have to learn. Now coming to Windows. Why does everything about Windows Development try to scare me away? It's basically come down to: USE C# AND .NET OR DIE. I don't like C#, I like C, they are fundamentally different. Yet when I make a Windows Forms application in MSVC++ (I know that's not C), I get a main function riddled with weird things I've never heard of before, along with a poor, barely-compliant C/C++ compiler. What am I to do when I just want to program in C, make applications that look and feel like native Windows applications (I am a sucker for aesthetics, and I'm not looking to make something cross-platform. I just want it to work on Windows, and look as native as possible.). C++ is a fine alternative, but it really looks like the only way to make a decent, native feeling Windows application, is to use C#. Am I missing something here? I'd rather not use CYGWIN. Like I said, I want people to install the program, and it should just work out of the box on Windows 7. Program in question involves a Media Player, if anyone is curious what I'm targetting at. Anyone who had the same experiences who can help me out? How can I code something in ANSI C and still have a native feel?

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  • Are high office partitions as effective as private offices?

    - by CraigS
    I'm currently reading DeMarco and Lister's Peopleware, and I've been struck (as everyone is) by their comments about noise reduction via using private offices, and the effect this has on productivity. Private offices are probably not going to happen at my workplace, but I'm wondering if high cubicle partitions (say, 6 feet) might be nearly as good? I imagine they wouldn't deflect quite as much noise, but they would have some effect. One down-side is that the center cubicles would have less natural light. That seems quite a big downer to me. I'd be interested to hear what peoples experiences are.

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  • Providing feedback on the Solaris Studio 12.4 Beta

    - by Darryl Gove
    Obviously, the point of the Solaris Studio 12.4 Beta programme was for everyone to try out the new version of the compiler and tools, and for us to gather feedback on what was working, what was broken, and what was missing. We've had lots of useful feedback - you can see some of it on the forums. But we're after more. Hence we have a Solaris Studio 12.4 Beta survey where you can tell us more about your experiences. Your comments are really helpful to us. Thanks.

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  • Library order is important

    - by Darryl Gove
    I've written quite extensively about link ordering issues, but I've not discussed the interaction between archive libraries and shared libraries. So let's take a simple program that calls a maths library function: #include <math.h int main() { for (int i=0; i<10000000; i++) { sin(i); } } We compile and run it to get the following performance: bash-3.2$ cc -g -O fp.c -lm bash-3.2$ timex ./a.out real 6.06 user 6.04 sys 0.01 Now most people will have heard of the optimised maths library which is added by the flag -xlibmopt. This contains optimised versions of key mathematical functions, in this instance, using the library doubles performance: bash-3.2$ cc -g -O -xlibmopt fp.c -lm bash-3.2$ timex ./a.out real 2.70 user 2.69 sys 0.00 The optimised maths library is provided as an archive library (libmopt.a), and the driver adds it to the link line just before the maths library - this causes the linker to pick the definitions provided by the static library in preference to those provided by libm. We can see the processing by asking the compiler to print out the link line: bash-3.2$ cc -### -g -O -xlibmopt fp.c -lm /usr/ccs/bin/ld ... fp.o -lmopt -lm -o a.out... The flag to the linker is -lmopt, and this is placed before the -lm flag. So what happens when the -lm flag is in the wrong place on the command line: bash-3.2$ cc -g -O -xlibmopt -lm fp.c bash-3.2$ timex ./a.out real 6.02 user 6.01 sys 0.01 If the -lm flag is before the source file (or object file for that matter), we get the slower performance from the system maths library. Why's that? If we look at the link line we can see the following ordering: /usr/ccs/bin/ld ... -lmopt -lm fp.o -o a.out So the optimised maths library is still placed before the system maths library, but the object file is placed afterwards. This would be ok if the optimised maths library were a shared library, but it is not - instead it's an archive library, and archive library processing is different - as described in the linker and library guide: "The link-editor searches an archive only to resolve undefined or tentative external references that have previously been encountered." An archive library can only be used resolve symbols that are outstanding at that point in the link processing. When fp.o is placed before the libmopt.a archive library, then the linker has an unresolved symbol defined in fp.o, and it will search the archive library to resolve that symbol. If the archive library is placed before fp.o then there are no unresolved symbols at that point, and so the linker doesn't need to use the archive library. This is why libmopt needs to be placed after the object files on the link line. On the other hand if the linker has observed any shared libraries, then at any point these are checked for any unresolved symbols. The consequence of this is that once the linker "sees" libm it will resolve any symbols it can to that library, and it will not check the archive library to resolve them. This is why libmopt needs to be placed before libm on the link line. This leads to the following order for placing files on the link line: Object files Archive libraries Shared libraries If you use this order, then things will consistently get resolved to the archive libraries rather than to the shared libaries.

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