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• Is there any open source tool that automatically 'detects' email threading like Gmail?

  - by Chris W.

  For instance, if the original message (message 1) is... Hey Jon, Want to go get some pizza? -Bill And the reply (message 2) is... Bill, Sorry, I can't make lunch today. Jonathon Parks, CTO Acme Systems On Wed, Feb 24, 2010 at 4:43 PM, Bill Waters wrote: Hey John, Want to go get some pizza? -Bill In Gmail, the system (a) detects that message 2 is a reply to message 1 and turns this into a 'thread' of sorts and (b) detects where the replied portion of the message actually is and hides it from the user. (In this case the hidden portion would start at "On Wed, Feb..." and continue to the end of the message.) Obviously, in this simple example it would be easy to detect the "On <Date, <Name wrote:" or the "" character prefixes. But many email systems have many different style of marking replies (not to mention HTML emails). I get the feeling that you would have to have some damn smart string parsing algorithms to get anywhere near how good GMail's is. Does this technology already exist in an open source project somewhere? Either in some library devoted to this exclusively or perhaps in some open source email client that does similar message threading? Thanks.

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• Get JVM to grow memory demand as needed up to size of VM limit?

  - by Ira Baxter

  We ship a Java application whose memory demand can vary quite a lot depending on the size of the data it is processing. If you don't set the max VM (virtual memory) size, quite often the JVM quits with an GC failure on big data. What we'd like to see, is the JVM requesting more memory, as GC fails to provide enough, until the total available VM is exhausted. e.g., start with 128Mb, and increase geometrically (or some other step) whenever the GC failed. The JVM ("Java") command line allows explicit setting of max VM sizes (various -Xm* commands), and you'd think that would be designed to be adequate. We try to do this in a .cmd file that we ship with the application. But if you pick any specific number, you get one of two bad behaviors: 1) if your number is small enough to work on most target systems (e.g., 1Gb), it isn't big enough for big data, or 2) if you make it very large, the JVM refuses to run on those systems whose actual VM is smaller than specified. How does one set up Java to use the available VM when needed, without knowing that number in advance, and without grabbing it all on startup?

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• perl multiple tasks problem

  - by Alice Wozownik

  I have finished my earlier multithreaded program that uses perl threads and it works on my system. The problem is that on some systems that it needs to run on, thread support is not compiled into perl and I cannot install additional packages. I therefore need to use something other than threads, and I am moving my code to using fork(). This works on my windows system in starting the subtasks. A few problems: How to determine when the child process exits? I created new threads when the thread count was below a certain value, I need to keep track of how many threads are running. For processes, how do I know when one exits so I can keep track of how many exist at the time, incrementing a counter when one is created and decrementing when one exits? Is file I/O using handles obtained with OPEN when opened by the parent process safe in the child process? I need to append to a file for each of the child processes, is this safe on unix as well. Is there any alternative to fork and threads? I tried use Parallel::ForkManager, but that isn't installed on my system (use Parallel::ForkManager; gave an error) and I absolutely require that my perl script work on all unix/windows systems without installing any additional modules.

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• Selectively intercepting methods using autofac and dynamicproxy2

  - by Mark Simpson

  I'm currently doing a bit of experimenting using Autofac-1.4.5.676, autofac contrib and castle DynamicProxy2. The goal is to create a coarse-grained profiler that can intercept calls to specific methods of a particular interface. The problem: I have everything working perfectly apart from the selective part. I gather that I need to marry up my interceptor with an IProxyGenerationHook implementation, but I can't figure out how to do this. My code looks something like this: The interface that is to be intercepted & profiled (note that I only care about profiling the Update() method) public interface ISomeSystemToMonitor { void Update(); // this is the one I want to profile void SomeOtherMethodWeDontCareAboutProfiling(); } Now, when I register my systems with the container, I do the following: // Register interceptor gubbins builder.RegisterModule(new FlexibleInterceptionModule()); builder.Register<PerformanceInterceptor>(); // Register systems (just one in this example) builder.Register<AudioSystem>() .As<ISomeSystemToMonitor>) .InterceptedBy(typeof(PerformanceInterceptor)); All ISomeSystemToMonitor instances pulled out of the container are intercepted and profiled as desired, other than the fact that it will intercept all of its methods, not just the Update method. Now, how can I extend this to exclude all methods other than Update()? As I said, I don't understand how I'm meant to say "for the ProfileInterceptor, use this implementation of IProxyHookGenerator". All help appreciated, cheers! Also, please note that I can't upgrade to autofac2.x right now; I'm stuck with 1.

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• Scaling Literate Programming?

  - by Tetha

  Greetings. I have been looking at Literate Programming a bit now, and I do like the idea behind it: you basically write a little paper about your code and write down as much of the design decisions, the code probably surrounding the module, the inner workins of the module, assumptions and conclusions resulting from the design decisions, potential extension, all this can be written down in a nice way using tex. Granted, the first point: it is documentation. It must be kept up-to-date, but that should not be that bad, because your change should have a justification and you can write that down. However, how does Literate Programming Scale to a larger degree? Overall, Literate Programming is still just text. Very human readable text, of course, but still text, and thus, it is hard to follow large systems. For example, I reworked large parts of my compiler to use and some magic to chain compile steps together, because some "x.register_follower(y); y.register_follower(z); y.register_follower(a);..." got really unwieldy, and changing that to x y z a made it a bit better, even though this is at its breaking point, too. So, how does Literate Programming scale to larger systems? Does anyone try to do that? My thought would be to use LP to specify components that communicate with each other using event streams and chain all of these together using a subset of graphviz. This would be a fairly natural extension to LP, as you can extract a documentation -- a dataflow diagram -- from the net and also generate code from it really well. What do you think of it? -- Tetha.

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• Linux Lightweight Distro and X Windows for Development

  - by Fernando Barrocal

  Heyall... I want to build a lightweight linux configuration to use for development. The first idea is to use it inside a Virtual Machine under Windows, or old Laptops with 1Gb RAM top. Maybe even a distributable environment for developers. So the whole idea is to use a LAMP server, Java Application Server (Tomcat or Jetty) and X Windows (any Window manager, from FVWM to Enlightment), Eclipse, maybe jEdit and of course Firefox. Edit: I am changing this post to compile a possible list of distros and window managers that can be used to configure a real lightweight development environment. I am using as base personal experiences on this matter. Info about the distros can be easily found in their sites. So please, focus on personal use of those systems Distros Ubuntu / Xubuntu Pros: Personal Experience in old systems or low RAM environment - @Schroeder, @SCdF Several sugestions based on personal knowledge - @Kyle, @Peter Hoffmann Gentoo Pros: Not targeted to Desktop Users - @paan Don't come with a huge ammount of applications - @paan Slackware Pros: Suggested as best performance in a wise install/configuration - @Ryan Damn Small Linux Pros: Main focus is the lightweight factor - 50MB LiveCD - @Ryan Debian Pros: Very versatile, can be configured for both heavy and lightweight computers - @Ryan APT as package manager - @Kyle Based on compatibility and usability - @Kyle -- Fell Free to add Prós and Cons on this, so we can compile a good Reference. -- X Windows suggestion keep coming about XFCE. If others are to add here, open a session for it Like the distro one :)

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• Bare-metal virtualisation for the desktop

  - by Andrew Taylor

  Hi, Does anyone have any knowledge about bare-metal virtualisation products? I'm interested in building a new desktop machine for home, I've been looking at the Intel Quad Core processors and I'd like to put 8GB of RAM in there, but, it got me thinking about making the most out of the available resources. I thought if I could get a good 64bit machine, put some bare-metal virtualisation on, then have a primary system, I'd also be able to bring up some extra virtualised systems as and when I needed. I know most of the bare metal systems are designed for the server market, but, is there anything out there that works well for a desktop. What are the caveats? I presume I won't be able to make the most out of any video cards I could buy, what about just getting a decent screen resolution, will this be a problem? I run a single 24" screen. What about DVD/CD writing, is this possible? I'd like to re-rip my CD collection, I was hoping the quad 64Bit goodness would help me out with the encoding. I currently use a Mac and couldn't go back to windows so that leaves Linux, I was thinking a primary OS of ubuntu. Does this make a difference? Thanks Andrew

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• Why is Microsoft under-supporting or under-developping VBNET?

  - by Will Marcouiller

  I ran into a situation where the lack of some features has become somewhat frustrating while developping in VB.NET 2.0. Since my first day of programming, I've always been a C programmer, and still am. Naturally, I chose C# as my favorite .NET language. Recently, a customer of mine has obliged that all of his development projects which disregard SharePoint development have to be written in VB.NET 2.0, that is to avoid conflictual systems to come into some problems. That is a legitimate choice of his which I approve somehow, since he's running some old central systems and is slowly migrating toward latest technologies. As for me, I would have prefered to go with C#, but then, never having done much VB in my life, I see it as an opportunity to learn somethings new, how to handle this and that in VBNET, etc. Except that the syntax is really too verbose for me, which is a pain! I got used to it and that is fine. However, I recently wanted to use the InternalsVisibleToAttribute which I discovered lastly here on SO. But then, in addition to not being able to have lambda expression that returns no value, which I discovered months ago, today I learn that I can't use the attribute in VBNET! Here is what I have read in an article: [...] Sorry VB.Net developers, Microsoft is again shunning you guys and this attribute is NOT available to you.... :( And here is the link: InternalsVisibleTo: Testing internal methods in .Net 2.0 I have heard from Anders Hejlsberg mouth while watching a Webcast from his presentation of .NET 4.0 Framework that the VBNET team was working or has worked in collaboration with the C# team (Eric Lippert and others) in order to bring VBNET to offer the same features as C# offers. But then, I say to myself that the VBNET team has a huge step forward to make, if already in .NET 2.0, some of the most important features lacked! So my question is this: Why is Microsoft under-supporting or under-developping VBNET? Will VBNET ever be lacking the C# features?

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• What is the best way to determine the path to the ISV directory?

  - by Luke Baulch

  MSCRM 4.0 Problem: I'm currently storing xml files in the ISV directory along with my web applications. From a plugin (or potentially a seperate app), I need to find an easy way to navigate to the ISV directory to read these xml files. This routine will be called extremely often, so processing minimization should be a strong consideration. Potential solutions: Registry: There is a registry key called 'WebSitePath' with the data 'C:\Inetpub\wwwroot\CRM'. Could potentially use this to build the path. (Will this be the same on all systems/installations?) IIS directory data: Looping through the DirectoryEntries of path '"IIS://localhost/W3SVC"' I could obtain the the web application where description is equal to "Microsoft Dynamics CRM". (Will this be the same on all systems/installations?) Webservice: Create one to read and return the data contained in these xml files The webservice would have easy access to its executing directory. Database: Store the data of these files in the database. Help: Can anyone suggest a simpler solution to obtaining and reading a file from the ISV directory? If not, which of the above solutions would be the quickest to process? Thanks for any and all contributions.

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• Testing a wide variety of computers with a small company

  - by Tom the Junglist

  Hello everyone, I work for a small dotcom which will soon be launching a reasonably-complicated Windows program. We have uncovered a number of "WTF?" type scenarios that have turned up as the program has been passed around to the various not-technical-types that we've been unable to replicate. One of the biggest problems we're facing is that of testing: there are a total of three programmers -- only one working on this particular project, me -- no testers, and a handful of assorted other staff (sales, etc). We are also geographically isolated. The "testing lab" consists of a handful of VMWare and VPC images running sort-of fresh installs of Windows XP and Vista, which runs on my personal computer. The non-technical types try to be helpful when problems arise, we have trained them on how to most effectively report problems, and the software itself sports a wide array of diagnostic features, but since they aren't computer nerds like us their reporting is only so useful, and arranging remote control sessions to dig into the guts of their computers is time-consuming. I am looking for resources that allow us to amplify our testing abilities without having to put together an actual lab and hire beta testers. My boss mentioned rental VPS services and asked me to look in to them, however they are still largely very much self-service and I was wondering if there were any better ways. How have you, or any other companies in a similar situation handled this sort of thing? EDIT: According to the lingo, our goal here is to expand our systems testing capacity via an elastic computing platform such as Amazon EC2. At this point I am not sure suggestions of beefing up our unit/integration testing are going to help very much as we are consistently hitting walls at the systems testing phase. Has anyone attempted to do this kind of software testing on a cloud-type service like EC2? Tom

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• Application log aggregation, management and notifications...

  - by Matthew Savage

  I'm wondering what everyone is using for logging, log management and log aggregation on their systems. I am working in a company which uses .NET for all it's applications and all systems are Windows based. Currently each application looks after its own logging and notifications of failures (e.g. if app A fails it will send out its own 'call for help' to an admin). While this current practice works its a bit hacky and hard to manage. I've been trying to find some options for making this work better and I've come up with the following: log4net & Chainsaw (ah, if it works). Logging via log4net or another framework into a central database & rolling our own management tool. Logging to the Windows event log and using MOM or System Center Operations Manager to aggregate and manage each of these servers & their apps. A hand-rolled solution to suck all the log files into one point and work some magic across them. Essentially what we are after is something which can pull log entries all together and allow for some analytics to be run across them, plus use a kind of event based system to, for example, send out a warning email when there have been 30+ warning level logs for an application in the last x minutes. So is there anything I've missed, or something someone else can suggest?

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• Method return type

  - by sarah xia

  Hi, In my company, a system is designed to have 3 layers. Layer1 is responsible for business logic handling. Layer3 is calling back end systems. Layer2 sits between the two layers so that layer1 doesn't need to know about the back end systems. To replay information from layer3, layer2 needs to define interface to layer1. For example, layer1 wants to check if a PIN from user is correct. It calls layer2 checkPin() method and then layer2 calls the relevant back end system. The checkPin() results could be: correctPin, inCorrectPin and internalError. At the moment, we defined the return type 'int'. So if layer2 returns 0, it means correctPin; if 1 is returned, it means inCorrectPin; if 9 is returned it means internalError. It works. However I feel a bit uneasy about this approach. Are there better ways to do it? For example define an enum CheckPinResult{CORRECT_PIN,INCORRECT_PIN,INTERNAL_ERROR}, and return CheckPinResult type? Thanks, Sarah

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• Alternative to Galileo GWS

  - by Anton Gogolev

  Please note that this Galileo is absolutely not related to Java. Galileo is basically a set of web services which can be used to book airline tickets. Originally, it was supposed to be used via Galileo Desktop, whereby operators would enter various commands to perform required operations. For example, SA*AZ610J20JULFCOJFK will "Display seat availability map for specified flight and class". Granted, humans can get used to it and be very efficient, but here comes a problem of integrating this with other systems. For that, folks at TravelPort basically slapped a SOAP interface to this system (which must have been written in COBOL or something), without even thinking about actually embracing XML. For example, it can contain <Ind1>N</Ind1> <Ind2>N</Ind2> <Ind3>N</Ind3> ... <Ind72>N</Ind72> <!-- Yes! 72! --> or, better yet <Text>P/RU/4xxx24528/RU/11MAY67/M/23DEC12/AxxxxxxV/MxxxM</Text> In light of this, my question is as follows: are there any sane airline tickets booking systems we can integrate with? Or are there companies which have products that can abstract away all this?

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• DVCS with a Windows central repository

  - by Mikko Rantanen

  We are currently using VSS for version control. Quite few of our developers are interested in a distributed model (And want to get rid of VSS). Our network is full of Windows machines and while our IT department has experience maintaining Linux machines they would prefer not to. What DVCS systems can host their central repository on Windows while providing.. Push access to the repository. Basic authentication. Mostly just a way to allow or deny access to the whole repository. No need for fine grained access. Server process so users don't need write right to the repository reducing the risk of accidentally messing with it. On the client side a GUI such as Tortoise would be more or less a requirement (Sorry, Windows shell sucks. :|). Ease of installation would be a huge plus as our IT department is already quite low on resources. And using windows credentials for authentication would be an advantage but not a requirement as long as the client is able to store the credentials. I have had a (really) quick look at Git, Mercurial and Bazaar. Git seemed to use ssh or simple WebDAV for repository access, requiring write permission for the users. Mercurial had a built in http server, but this seemed to be only for pull purposes. Update: Mercurial supports push as well. Bazaar Seemed to use sftp for repository access, again requiring a write permission for the users. Are there windows server processes for any DVCS systems and has anyone managed to set one up in a Windows land? And apologies if this is a duplicate question. I couldn't find one. Update Got Mercurial working for push purposes! Detailed list what was required can be found as an answer below.

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• Biztalk vs API for databroker layer

  - by jdt199

  My company is about to undergo a large project in which our client wants a large customer portal with a cms, crm implementing. This will require interaction with data from multiple sources across our customers business, these sources include XML office backend systems, sql datbases, webservices etc. Our proposed solution would be to write an API in c# to provide a common interface with all these systems. This would be scalable for future and concurrent projects within the company. Our client expressed an interest in using Biztalk rather than a custom API for this integration, as they feel it is an enterprise solution that any of their suppliers could pick up and use, and it will be better supported. We feel that the configuration work using Biztalk would be rather heavy for all their custom business rules which are required and an interface for the new application to get data to and from Biztalk would still need to be written. Are we right to prefer a custom API solution above Biztalk? Would Biztalk be suitable as a databroker layer to provide an interface for the new Customer portal we are writing. We have not experience with using Biztalk before so any input would be appreciated.

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• Creating an SQL variable character column > 255 characters supporting multiple databases

  - by Piers

  I have an application that stores data through an ODBC data source of the user's choosing. So far it has worked well on a range of database systems (e.g. JET, Oracle, SQL Server), as the SQL syntax is fairly simple. Now I am running into a problem where I need to store more than 255 characters in my strings. Previously I created the table using column type VARCHAR (255). Now if I try to create a table using, e.g. VARCHAR (512) then it falls over on Access databases. I know that I can use the MEMO type for Access, but this is non-standard SQL and will thus likely fail on other database systems (e.g. Oracle). Is there any widely supported SQL standard for creating text columns wider than 255 characters, or do I need to find another solution? The alternatives seem to me to be: 1) Profile the database system and customise the SQL CREATE TABLE command based on the database system. I don't like this as it defeats the purpose of using ODBC. 2) Add extra columns of 255 chars as required (e.g. LONGSTRING1, LONGSTRING2, ...) and concatenate after reading. I don't like this because it means the number of columns can vary between tables and it complicates read/write. Are there any other viable alternatives to these two options? Or is it possible to have an SQL compliant CREATE TABLE command supported by the majority of database vendors, that supports strings longer than 255 chars?

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• Choosing between .NET Service Bus Queues vs Azure Queue Service

  - by ChrisV

  Just a quick question regarding an Azure application. If I have a number of Web and Worker roles that need to communicate, documentation says to use the Azure Queue Service. However, I've just read that the new .NET Service Bus now also offers queues. These look to be more powerful as they appear to offer a much more detailed API. Whilst the .NSB looks more interesting it has a couple of issues that make me wary of using it in distributed application. (for example, Queue Expiration... if I cannot guarantee that a queue will be renewed on time I may lose it all!). Has anyone had any experience using either of these two technologies and could give any advice on when to choose one over the other. I suspect that whilst the service bus looks more powerful, as my use case is really just enabling Web/Worker roles to communicate between each other, that the Azure Queue Service is what I'm after. But I'm just really looking for confirmation of that before progamming myself in to a corner :-) Thanks in advance. UPDATE Have read up about the two systems over the break. It defo looks like .NET service bus is more specifically designed for integrating systems rather than providing a general purpose reliable messaging system. Azure Queues are distributed and so reliable and scalable in a way that .NSB queues are not and so more suitable for code hosted within Azure itself. Thanks for the responses.

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• Why am I getting a ParseException when using SimpleDateFormat to format a date and then parse it?

  - by Greg

  I have been debugging some existing code for which unit tests are failing on my system, but not on colleagues' systems. The root cause is that SimpleDateFormat is throwing ParseExceptions when parsing dates that should be parseable. I created a unit test that demonstrates the code that is failing on my system: import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; import java.util.TimeZone; import junit.framework.TestCase; public class FormatsTest extends TestCase { public void testParse() throws ParseException { DateFormat formatter = new SimpleDateFormat("yyyyMMddHHmmss.SSS Z"); formatter.setTimeZone(TimeZone.getDefault()); formatter.setLenient(false); formatter.parse(formatter.format(new Date())); } } This test throws a ParseException on my system, but runs successfully on other systems. java.text.ParseException: Unparseable date: "20100603100243.118 -0600" at java.text.DateFormat.parse(DateFormat.java:352) at FormatsTest.testParse(FormatsTest.java:16) I have found that I can setLenient(true) and the test will succeed. The setLenient(false) is what is used in the production code that this test mimics, so I don't want to change it.

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• Automated Legal Processing

  - by Chris S

  Will it ever be possible to make legal systems quantifiable enough to process with computer algorithms? What technologies would have to be in place before this is possible? Are there any existing technologies that are already trying to accomplish this? Out of curiosity, I downloaded the text for laws in my local municipality, and tried applying some simple NLP tricks to extract rules from sentences. I had mixed results. Some sentences were very explicit (e.g. "Cars may not be left in the park overnight"), but other sentences seemed hopelessly vague (e.g. "The council's purpose is to ensure the well-being of the community"). I apologize if this is too open-ended a topic, but I've often wondered what society would look like if legal systems were based on less ambiguous language. Lawyers, and the legal process in general, are so expensive because they have to manually process a complex set of rules codified in ambiguous legal texts. If this system could be represented in software, this huge expense could potentially be eliminated, making the legal system more accessible for everyone.

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• Needed environment for building gstreamer plugins in Windows

  - by utnapistim

  Hi, I've been strugling for two weeks to create an environment for building a gstreamer plugin on windows (needed for a songbird addon). I've installed MSYS, MinGW and Cygwin, then installed GStreamer OSSBuild, and I also downloaded the sources for Songbird, which come with their own precompiled version of gstreamer. I was unable to run gst-inspect (or any other gstreamer applications) from the songbird sources and I figured I will settle for OSSBuild. When following the instructions for building a GST plugin (found here) through, cygwin will not recognize the OSSBuild and the build fails when running autogen, with the following error: checking for GST... no configure: error: You need to install or upgrade the GStreamer development packages on your system. On debian-based systems these are libgstreamer0.10-dev and libgstreamer-plugins-base0.10-dev. on RPM-based systems gstreamer0.10-devel, libgstreamer0.10-devel or similar. The minimum version required is 0.10.16. configure failed I could also not use MSYS or MinGW as they are unable to run autogen at all. I understand that cygwin should have it's own gstreamer development packages but I couldn't find how to install them. My question: How do I install the gstreamer packages in cygwin or how do I build using cygwin with the OSSBuild dependencies? In short, how do I get an environment where I can build a gstreamer plugin under windows?

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• Is A Web App Feasible For A Heavy Use Data Entry System?

  - by Rob

  Looking for opinions on this, we're working on a project that is essentially a data entry system for a production line. Heavy data input by users who normally work in Excel or other thick client data systems. We've been told (as a consequence) that we have to develop this as a thick client using .NET. Our argument was to develop as a web app, as it resolves a lot of issues and would be easier to write and maintain. Their argument against the web is that (supposedly) the web is not ready yet for a heavy duty data entry system, and that the web in a browser does not offer the speed, responsiveness, and fluid experience for the end-user that a thick client can (citing things such as drag and drop, rapid auto-entry and data navigation, etc.) Personally, I think that with good form design and JQuery/AJAX, a web app could do everything a thick client does just as well, and they just don't know what they're talking about. The irony is that a thick client has to go to a lot more effort to manage the deployment and connectivity back to the central data server than a web app would need to do, so in terms of speed I would expect a web app to be faster. What are the thoughts of those out there? Are there any technologies currently in production use that modern data entry systems are being developed as web apps in? Appreciate any feedback. Regards, Rob.

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• Using hashing to group similar records

  - by Neil Dobson

  I work for a fulfillment company and we have to pack and ship many orders from our warehouse to customers. To improve efficiency we would like to group identical orders and pack these in the most optimum way. By identical I mean having the same number of order lines containing the same SKUs and same order quantities. To achieve this I was thinking about hashing each order. We can then group by hash to quickly see which orders are the same. We are moving from an Access database to a PostgreSQL database and we have .NET based systems for data loading and general order processing systems, so we can either do the hashing during the data loading or hand this task over to the DB. My question firstly is should the hashing be managed by DB, possibly using triggers, or should the hash be created on-the-fly using a view or something? And secondly would it be best to calculate a hash for each order line and then to combine these to find an order-level hash for grouping, or should I just use a trigger for all CRUD operations on the order lines table which re-calculates a single hash for the entire order and store the value in the orders table? TIA

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• How to benchmark on multi-core processors

  - by Pascal Cuoq

  I am looking for ways to perform micro-benchmarks on multi-core processors. Context: At about the same time desktop processors introduced out-of-order execution that made performance hard to predict, they, perhaps not coincidentally, also introduced special instructions to get very precise timings. Example of these instructions are rdtsc on x86 and rftb on PowerPC. These instructions gave timings that were more precise than could ever be allowed by a system call, allowed programmers to micro-benchmark their hearts out, for better or for worse. On a yet more modern processor with several cores, some of which sleep some of the time, the counters are not synchronized between cores. We are told that rdtsc is no longer safe to use for benchmarking, but I must have been dozing off when we were explained the alternative solutions. Question: Some systems may save and restore the performance counter and provide an API call to read the proper sum. If you know what this call is for any operating system, please let us know in an answer. Some systems may allow to turn off cores, leaving only one running. I know Mac OS X Leopard does when the right Preference Pane is installed from the Developers Tools. Do you think that this make rdtsc safe to use again? More context: Please assume I know what I am doing when trying to do a micro-benchmark. If you are of the opinion that if an optimization's gains cannot be measured by timing the whole application, it's not worth optimizing, I agree with you, but I cannot time the whole application until the alternative data structure is finished, which will take a long time. In fact, if the micro-benchmark were not promising, I could decide to give up on the implementation now; I need figures to provide in a publication whose deadline I have no control over.

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• Controlling shell command line wildcard expansion in C or C++

  - by Adrian McCarthy

  I'm writing a program, foo, in C++. It's typically invoked on the command line like this: foo *.txt My main() receives the arguments in the normal way. On many systems, argv[1] is literally *.txt, and I have to call system routines to do the wildcard expansion. On Unix systems, however, the shell expands the wildcard before invoking my program, and all of the matching filenames will be in argv. Suppose I wanted to add a switch to foo that causes it to recurse into subdirectories. foo -a *.txt would process all text files in the current directory and all of its subdirectories. I don't see how this is done, since, by the time my program gets a chance to see the -a, then shell has already done the expansion and the user's *.txt input is lost. Yet there are common Unix programs that work this way. How do they do it? In Unix land, how can I control the wildcard expansion? (Recursing through subdirectories is just one example. Ideally, I'm trying to understand the general solution to controlling the wildcard expansion.)

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• PHP package manager

  - by Mathias

  Hey, does anyone know a package manager library for PHP (as e.g. apt or yum for linux distros) apart from PEAR? I'm working on a system which should include a package management system for module management. I managed to get a working solution using PEAR, but using the PEAR client for anything else than managing a PEAR installation is not really the optimal solution as it's not designed for that. I would have to modify/extend it (e.g. to implement actions on installation/upgrade or to move PEAR specific files like lockfiles away from the system root) and especially the CLI client code is quite messy and PHP4. So maybe someone has some suggestions for an alternative PEAR client library which is easy to use and extend (the server side has some nice implementations like Pirum and pearhub) for completely different package management systems written in PHP (ideally including dependency tracking and different channels) for some general ideas how to implement such a PM system (yes, I'm still tinkering with the idea of implementing such a system from scratch) I know that big systems like Magento and symfony use PEAR for their PM. Magento uses a hacked version of the original PEAR client (which I'd like to avoid), symfony's implementation seems quite integrated with the framework, but would be a good starting point to at least write the client from scratch. Anyway, if anybody has suggestions: please :)

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