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• Disabling Remote-Debugging Connection on Windows 2000

  - by Kim Leeper

  I have two machines one running Win 2000 and one running Win XP both with VSC++ 6. I created an application on the Win XP machine (local) and sucessfuly used the Win2000 machine (remote) as the target for debugging. The code was in a shared drive on the Win2000 machine. This setup worked well, just like in the movies! However, I now wish to use my Win2000 machine as a develpment machine again and I find I can not. When attempting to execute a natively compiled application on this machine, I get a dialog with the title of "Remote Execution Path And Filename" asking me for same. When dialog is cancelled as the program that is attemptng to execute is not remote, the program terminates without error. Extra info! On the WinXP machine, VSC++, under the Build menu-Debugger Remote Connection-Remote Connection Dialog-the "Connection:" list box has two entries 'Local' and 'Network', on the Win2000 machine the 'Local' entry is not present, only the entry for 'Network'. How do I get back my 'Local' entry on what used to be my target machine?

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• Using TXMLDocument to serialize form settings to XML and database.

  - by LukLed

  I have an interface: type IXMLSerializable = interface function SaveToXML : DOMString; function SaveToXMLDocument : IXMLDocument; procedure LoadFromXML(AXML : DOMString); end; It is used to serialize some settings of forms or frames to xml. Simple implementation: SaveToXMLDocument: function TSomething.SaveToXMLDocument: IXMLDocument; begin Result := TXMLDocument.Create(nil); with Result do begin Active := True; with AddChild(Self.Name) do begin AddChild(edSomeTextBox.Name).Attributes['Text'] := edSomeTextBox.Text; end; end; Result := XMLDoc; end; LoadFromXML: procedure TSomething.LoadFromXML(AXML: DOMString); var XMLDoc : IXMLDocument; I : Integer; begin XMLDoc := TXMLDocument.Create(nil); with XMLDoc do begin LoadFromXML(AXML); Active := True; with ChildNodes[0] do begin for I := 0 to ChildNodes.Count-1 do begin If ChildNodes[I].NodeName = 'edSomeTextBox' then edSomeTextBox.Text := ChildNodes[I].Attributes['Text']; end; end; end; end; SaveToXML: function TSomething.SaveToXML: DOMString; begin SaveToXMLDocument.SaveToXML(Result); end; DOMString result of SaveToXML is saved to database to blob field. I had some encoding issues with other implementations and this one works fine (right now). Do you see any dangers in this code? Can I have issues with different settings on various machines and systems?

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• Anyone Experiencing Slow Builds With VS2010?

  - by MrKWatkins

  Hi, We've recently upgraded to the final release of VS2010 and are experiencing very slow build times compared to the same code under 2008. I was wondering if anyone else is experiencing the same so I can work out whether it's just our environment or not? A few details: Using VS2010 Ultimate on Windows 7 with fairly beefy machines, talking to TFS 2010. The solution has been upgraded from VS2008 but still builds against .NET 3.5 and ASP.NET MVC 1.0. It doesn't seem to be the compilation itself taking long but something else in the build process. This is because even projects that are up to date and don't need compiling are taking a few seconds or so to process. It's not due to an Visual Studio addin because a couple guys in the team haven't installed any. The first build after loading VS2010 is pretty quick, then they seem to slow down over time. For example on of the projects in my solution just took 00:00:00.08 to process after a restart. (The project was up to date and didn't need compiling) I then immediately hit rebuild and it jumps to 00:00:01.33. We're also experiencing the problem with another solution that uses .NET 4.0 that was building perfectly fine under VS2010 RC. There are no build events or anything like that I can blame, just straightforward assembly builds. The IDE is not very responsive during the slow builds. Anyone else has similar problems? Update: It looks like the resolving assembly references is taking a long time. Looking at the MSBuild diagnostic output or the example above the first build has 30ms for ResolveAssemblyReferences, the second build has 800ms. Subsequent builds seem to be taking longer copying stuff around, e.g. CopyFilesToOutputDirectory jumps from 1ms to 27ms.

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• Maven build issue with Hibernate for Windows

  - by wishi_

  Hi! I'm getting build errors for for my Maven enabled project related to the Hibernate extension. - It's a very basic app, and I was able to solve this issue on my Linux box by manually installing some required artifacts: mvn install:install-file -DgroupId=javassist -DartifactId=javassist -Dversion=3.9.0 -Dpackaging=jar -Dfile=foo.jar That worked out (Hibernate as a set of required deps). But in case of Windows things are different. How do I add the dependencies manually to Maven on Windows? 1) org.hibernate:hibernate:jar:3.3.2 Try downloading the file manually from the project website. Then, install it using the command: mvn install:install-file -DgroupId=org.hibernate -DartifactId=hibernate -Dversion=3.3.2 -Dpackaging=jar -Dfile=/path/to/file 2) javassist:javassist:jar:3.9.0 Can I automate this cumbersome manual dependency installation for my coworkers on their Windows machines? Are there any helpful tools or GUI that can perform these tasks? The best way would be that Maven does it all automatically. I'm not too familiar with it jet. Thanks for answers.

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• How to create a desktop shortcut to a website with website logo as icon?

  - by Wbdvlpr

  Hi I need a solution which allows users to create a desktop shortcut to a website, preferably with website logo as shortcut icon. There are ways users can create shortcut such as drag drop favicon or right click create new shortcut etc. This works but also creates the shortcut with default IE icon on windows. I am trying to avoid this method for this icon and some other reasons. I thought of creating a website-title.URL file, and tell users to download and save file to their desktop, again this works but doesn't solve the icon problem as the website logo (.ico) has to be at local disk and at a pre-specified location [IconFile=path]. I was wondering if it is possible to create a some sort of installer or windows application which users can download from the website. Once its executed by user, it creates this .URL file on user desktop which have IconFile path pre-specified, and copy the website-logo.ico at path specified in .URL file etc. So my questions are - Is it possible to create such a solution? What programming languages can be used to achieve this? Can this installer/app be made to work on non-windows machines as well? From developments point of view how big project it is? if I have to hire a programmer to do this. Please let me know if you need more information. Thanks

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• unbuffered I/O in Linux

  - by stuck

  I'm writing lots and lots of data that will not be read again for weeks - as my program runs the amount of free memory on the machine (displayed with 'free' or 'top') drops very quickly, the amount of memory my app uses does not increase - neither does the amount of memory used by other processes. This leads me to believe the memory is being consumed by the filesystems cache - since I do not intend to read this data for a long time I'm hoping to bypass the systems buffers, such that my data is written directly to disk. I dont have dreams of improving perf or being a super ninja, my hope is to give a hint to the filesystem that I'm not going to be coming back for this memory any time soon, so dont spend time optimizing for those cases. On Windows I've faced similar problems and fixed the problem using FILE_FLAG_NO_BUFFERING|FILE_FLAG_WRITE_THROUGH - the machines memory was not consumed by my app and the machine was more usable in general. I'm hoping to duplicate the improvements I've seen but on Linux. On Windows there is the restriction of writing in sector sized pieces, I'm happy with this restriction for the amount of gain I've measured. is there a similar way to do this in Linux?

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• VB6 ActiveX exe - what is the proper registration sequence?

  - by Timbuck

  I have recently updated a Visual Basic 6 application that is an ActiveX exe, running on Windows XP. I have a couple of testers for this application who have received a copy of the exe and are attempting to run it. However, they are getting an error message "Unexpected error;quitting" when trying to do so. A key difference between their testing and my testing is that on the machines I tested on, I have admin rights and was able to register the application using the appname.exe /regserver command line. Reading the details at MS Support about file registration appears unclear: Visual Basic ActiveX EXE files register themselves the first time you run the EXE. However, you cannot use the EXE as a COM server until it is registered. So does this mean that after the first time the users run the exe that the application should be correctly registered, and the error I am receiving is sign of something other than an incorrectly registered application? Or does this mean that the application will not work properly until such time as the file is explicitly registered using the appname.exe /regserver command line? nb - during a production distribution, the software would be sent out to client PCs using Systems Management Server, which isn't an option for this testing.

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• Creating and parsing huge strings with javascript?

  - by user246114

  Hi, I have a simple piece of data that I'm storing on a server, as a plain string. It is kind of ridiculous, but it looks like this: name|date|grade|description|name|date|grade|description|repeat for a long time this string can be up to 1.4mb in size. The idea is that it's a bunch of student records, just strung together with a simple pipe delimeter. It's a very poor serialization method. Once this massive string is pushed to the client, it is split along the pipes into student records again, using javascript. I've been timing how long it takes to create, and split, these strings on the client side. The times are actually quite good, the slowest run I've seen on a few different machines is 0.2 seconds for 10,000 'student records', which has a final string size of ~1.4mb. I realize this is quite bizarre, just wondering if there are any inherent problems with creating and splitting such large strings using javascript? I don't know how different browsers implement their javascript engines. I've tried this on the 'major' browsers, but don't know how this would perform on earlier versions of each. Yeah looking for any comments on this, this is more for fun than anything else! Thanks

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• What's a good way to do testing a plug-in on multiple Windows and Outlook versions?

  - by Andrei

  Hello, We're building a plug-in for Outlook that should work on multiple Windows versions (XP, Vista, 7) and also with different Outlook versions (2003, 2007, 2010). The testing problem I am facing right now, is that I can't figure out a good/convenient/thorough way to test the application on multiple Windows and Outlook versions. At the moment, I have a VirtualBox which runs many virtual machines, with different Windows versions and Outlook versions. So I would have a virtual machine with Windows 7 testing Outlook 2010, and another one with Windows 7 testing Outlook 2007, Windows Vista with Outlook 2010 and so on, going through some of the possible combinations. It kind of gets the job done, although it is cumbersome and takes a long time to test. Some of the testing included in the application is unit testing, but this is also rather tied in with the machine I test it on (windows 7 with outlook 2010). For example, I was using ManagementObject recently, which worked fine on my system (and thus passed the unit test for that method), however, using that object threw an exception in another person's system, which crashed the application. I work on Visual Studio 2010 Ultimate. The questions: Is there a more elegant way to make the testing process more streamline and more efficient? Any other testing methods you recommend? How would you deal with this problem? Thanks! Looking forward to your replies.

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• How to detect .NET WPF memory leak or GC long run?

  - by Néstor Sánchez A.

  I have the next very strange situation and problem: .NET 4.0 application for diagram editing (WPF). Runs ok in my PC: 8GM RAM, 3.0GHz, i7 quad-core. While creating objects (mostly diagram nodes and connectors, plus all the undo/redo information) the TaskManager show, as expected, some memory usage "jumps" (up and down). These mem-usage "jumps" also remains executing AFTER user interaction ended. Maybe this is the GC cleaning/regorganizing memory? To see what is going on, I've used the Ants mem profiler, but somewhat it prevents those "jumps" to happen after user interaction. PROBLEM: It Freezes/Hangs after seconds or minutes of usage in some slow/weak laptos/netbooks of my beta testers (under 2GHz of speed and under 2GB of RAM). I was thinking of a memory leak, but... EDIT: Also, there is the case that the memory usage grows and grows until collapse (only in slow machines). In a Windows XP Mode machine (VM in Win 7) with only 512MB of RAM Assigned it works fine without mem-usage "jumps" after user interaction (no GC cleaning?!). So, I really have a big trouble because I cannot reproduce the error, only see these strange behaviour (mem jumps), and the tool supposed to show me what is happening is hiding the problem (like the "observer's paradox"). Any ideas on what's happening and how to solve it?

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• how to seamlessly integrate subversion and git?

  - by mattv

  I'm looking for tips on how to seamlessly integrate subversion and git, for deploying web sites by a small team of web developers. We each have our own development versions of our sites on our local machines. We also have dev, staging, and live servers. As our team has grown, we haven't updated our revision control and deployment strategies accordingly. We had all been checking into the trunk of a shared Subversion repository. Both the dev & staging servers ran from a checkout of the trunk, so updating them involved running "svn update" while the live server ran as an export from trunk which required an "svn export" to get the latest code. In either case, we would often update just certain files by updating or exporting just those files or directories. That worked okay when there was just one or two developers. However, a big downside was that we couldn't point to an individual tag that represented what was currently on live at any given time. In keeping with corporate policy, we'd like to continue to use Subversion to store what we're now calling our "production branch," which will be what goes onto staging and live. However, we would like to use Git on our local and development sites. We especially like the idea of easier merges and being able to "cherry pick" updates that need to go live. We had initially planned on using git-svn, but it doesn't seem to work well in a shared environment such as our dev or staging servers. Anyone else doing something like this? What's the best way to make it work? Or are we making it more difficult than it should be?

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• Running a process at the Windows 7 Welcome Screen

  - by peelman

  So here's the scoop: I wrote a tiny C# app a while back that displays the hostname, ip address, imaged date, thaw status (we use DeepFreeze), current domain, and the current date/time, to display on the welcome screen of our Windows 7 lab machines. This was to replace our previous information block, which was set statically at startup and actually embedded text into the background, with something a little more dynamic and functional. The app uses a Timer to update the ip address, deepfreeze status, and clock every second, and it checks to see if a user has logged in and kills itself when it detects such a condition. If we just run it, via our startup script (set via group policy), it holds the script open and the machine never makes it to the login prompt. If we use something like the start or cmd commands to start it off under a separate shell/process, it runs until the startup script finishes, at which point Windows seems to clean up any and all child processes of the script. We're currently able to bypass that using psexec -s -d -i -x to fire it off, which lets it persist after the startup script is completed, but can be incredibly slow, adding anywhere between 5 seconds and over a minute to our startup time. We have experimented with using another C# app to start the process, via the Process class, using WMI Calls (Win32_Process and Win32_ProcessStartup) with various startup flags, etc, but all end with the same result of the script finishing and the info block process getting killed. I tinkered with rewriting the app as a service, but services were never designed to interact with the desktop, let alone the login window, and getting things operating in the right context never really seemed to work out. So for the question: Does anybody have a good way to accomplish this? Launch a task so that it would be independent of the startup script and run on top of the welcome screen?

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• Ignore all folders with a certain name in SVN (subversion), how to?

  - by Roeland

  I am fairly new to Subversion and was wondering how exactly to ignore all folders by a specific name. From what I have read, I think I need to use the svn:ignore function, but I have no clue on how to actually do this. Some places mention a config file.. some say command prompt. I have my subversion repo set up on a windows 2008 server. I tried to go to command prompt and type svn:ignore name but that didnt work. The tutorial I used to set up my repo (with apache 2.2) had me create an etc folder in c:/. There I have subversion.conf, svn-acl and svn-auth-file. My subversion.conf file includes this: <Location /btp> DAV svn SVNPath C:/Files/Work/Repositories/btp AuthType Basic AuthName "By The Pixel Repo" AuthUserFile c:/etc/svn-auth-file Require valid-user AuthzSVNAccessFile c:/etc/svn-acl </Location> The client I use for my development machines is tortoisesvn. Im a bit of a noob so any help is appreciated it! Thanks.

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• Cookies not working for password-protected Pages on WordPress

  - by KaOSoFt

  Initially I had the issue reported in this question. Now, what I noticed is that there are some browsers that accept the password, and there are some which don't. Difference? For some reason the cookie is generated when I log in into the Administration module, but it isn't when I write down the password to access the page, forcing it to simply reload. I can see the cookie created for the log-in, but I can see none for the password-protected Page. These happens on Internet Explorer, both version 7 and 8; only on some machines, though, but most of them fail this. I already tried white-listing the URL, and even letting it accept ALL cookies, to no avail. What may be the cause? If perhaps it's got something to do with question above, please help me! Thanks in advance. PS: If you know of another, cookie-free method to make a simple authentication, please link me to it. Thanks. Oh, and by the way, this is inside an Intranet with static, class C IPs.

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• how to trigger a script located on a machine in one domain from a machine on another domain

  - by user326814

  Hi, I am basically from QA. What we testers do each day is 1. Open a web browser. Type in http://11.12.13.27.8080/cruisecontrol (since we are in a particular network, only we can access this) 2. Check if the latest nightly build has been successful. If it is successful, deploy it on a test environment by clicking on 'Deploy this build' link. This deploying takes around 1-1.5 hours. During this time we cannot use our machines to work on anything else. Only after this deploying can we begin to test. Now, i wanted to know if its possible to do the below. When at home in the morning, i use something which will trigger a script (which will be on my machine at workplace). This script will inturn automatically deploy the build. I already have such a similar script. What i want to know is how is it possible to trigger this script from my home machine? Is it even possible? For e.g the external trigger will say "Deploy xxx branch on yyy test environment". So the script on my workplace machine will be invoked and it will automatically deploy it before i actually come to my desk. Please help. I am from QA and have no idea about all this.

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• Database solution for 200million writes/day, monthly summarization queries

  - by sb

  Hello. I'm looking for help deciding on which database system to use. (I've been googling and reading for the past few hours; it now seems worthwhile to ask for help from someone with firsthand knowledge.) I need to log around 200 million rows (or more) per 8 hour workday to a database, then perform weekly/monthly/yearly summary queries on that data. The summary queries would be for collecting data for things like billing statements, eg. "How many transactions of type A did each user run this month?" (could be more complex, but that's the general idea). I can spread the database amongst several machines, as necessary, but I don't think I can take old data offline. I'll definitely need to be able to query a month's worth of data, maybe a year. These queries would be for my own use, and wouldn't need to be generated in real-time for an end-user (they could run overnight, if needed). Does anyone have any suggestions as to which databases would be a good fit? P.S. Cassandra looks like it would have no problem handling the writes, but what about the huge monthly table scans? Is anyone familiar with Cassandra/Hadoop MapReduce performance?

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• Setting up a git repository on a server

  - by lostInTransit

  Hi I had posted this question on superuser but didn't get a helpful response. Thought I'd try here since the question does deal with some configurations and settings for using github. I have a central server with SSO installed. All my machines are connected through the lan to this server. I have also setup a remote git repository on this server. Now what I'd like to do is make the server act as a central repository. All my employees can commit their code to the server and the server pushes it to the remote git repository. Can someone please help me out with this process? I am new to git and still learning how to use it effectively. So a step-by-step process or an existing document which I can refer to for this? Also can I integrate it with SSO in any way? The server itself is setup on a Mac and SSO uses Atlassian Crowd. Thanks.

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• PHP transfer files from server to server in LAN

  - by cheapez

  So, I have 5-6 pages of requirements. I'm trying to build this application in PHP based on the requirements. I want to transfer files from one server to the other server in LAN, and then send a shell command to the other server to find out if the file has been transferred successfully. In php, I can transfer files using FTP, and send shell commands using SSH. Using the methods above, I will need to open connection to the server first, but I don't know the ftp server name, domain name, ip address, or anything like that. I only know the the server ID (I'm not sure what this ID is, but I guess it is like the computer's name). An example of the server ID is: "c23bap234" How do I open a connection with just that server ID? These servers are in the same building, have LAN connection, don't have connection to the outside world. These machines have PHP, Apache, ... installed. If my post doesn't make sense to you, it's because I'm a learner. I hope someone can help me on this. Thanks in advance.

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• Need help managing MySql connections

  - by David Jenings

  I'm having trouble finding a clear explanation of connection pooling. I'm building an app using the .NET connector I downloaded from mysql.com. The app only needs one db connection but will be running simultaneously on about 6 machines on my network. Normally, I'd create the connection at startup and just leave it. But I'm seeing lots of posts from people who say that's bad practice. Also I'm concerned about timeouts. My app will run 24/7 and there may be extended periods without database activity. I'm leaning toward the following: using (MySqlConnection conn = new MySqlConnection(connStr)) { conn.Open(); // use connection } But I'm not sure I understand what's going on in the background. Is this actually closing the connection and allowing gc to kill the object, or is there a built in pooling behavior that preserves the object and redelivers it the next time I try to create one? I certainly don't want the app reauthenticating across the network every time I hit the database. Can anyone offer me some advise?

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• Is it possible to reference remote content from chrome.manifest? (XULRunner)

  - by siemaa

  Hi, I have a xulrunner application and I've been trying to reference remote content from chrome.manifest file. Tt's an application for the company I work in; it's run on a number of computers (most of them are used by other employees as well) as a kind of an internet monitoring service. The problem I'd like to solve is this: updating the code of such application usually requires me to manually copy the modified files to every computer that the application is running on (I've had no luck trying to make automatic updates via xulrunner platform). This process has become very tedious. What I'd like to have is a web server, where all of the xul and js files would be accessible, so that every application could reference them from there. This would require me only to update the code on that server, and the applications (when restarted) would automatically get the latest code. What I managed to do: I can reference js scripts from a xul file using http based urls and everything works fine (I can use local, binary components etc.), although the xul file has to be local - that I'd like to change. But when I write in chrome.manifest a line like: content my_app http://path/to/app/files/ and then use the line in default/preferences/pref.js pref("toolkit.defaultChromeURI", "chrome://my_app/content/my_app.xul"); it just opens a console window (to test I manually run the application with the -console option) and no code gets executed. The file can be downloaded remotely using wget so I guess this isn't the web server issue. The applications work on Windows machines. Is there some kind of security issue causing such behavior or am I doing something wrong? Is it even possible to register remote, http based content as chrome?

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• Is it possible to get a truly unique id for a particular JVM instance?

  - by Uri

  I need a way to uniquely and permanently identify an instance of the JVM from within Java code running in that JVM. That is, if I have two JVMs running at the same time on the same machine, each is distinguishable. It is also distinguishable from running JVMs on other machines and from future executions on the same machine even if the process id is reused. I figure I could implement something like this by identifying the start time, the machine MAC, and the process id, and combining them in some way. I'm wondering if there is some standard way to achieve this. Update: I see that everyone recommended a UUID for the entire session. That seems like a good idea though possibly a little too heavyweight. Here is my problem though: I want to use the JVM id to create multiple unique identifiers in each JVM execution that somehow incorporate the JVM instance. My understanding is that you shouldn't really mix other numbers into a UUID because uniqueness is no longer guaranteed. An alternative is to make the UUID into a string and chain it, but then it becomes too long. Any ideas on overcoming this?

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• Log4j Logging to the Wrong Directory

  - by John

  I have a relatively complex log4j.xml configuration file with many appenders. Some machines the application runs on need a separate log directory, which is actually a mapped network drive. To get around this, we embed a system property as part of the filename in order to specify the directory. Here is an example: The "${user.dir}" part is set as a system property on each system, and is normally set to the root directory of the application. On some systems, this location is not the root of the application. The problem is that there is always one appender where this is not set, and the file appears not to write to the mapped drive. The rest of the appenders do write to the correct location per the system property. As a unit test, I set up our QA lab to hard-code the values for the appender above, and it worked: however, a different appender will then append to the wrong file. The mis-logged file is always the same for a given configuration: it is not a random file each time. My best educated guess is that there is a HashMap somewhere containing these appenders, and for some reason, the first one retrieved from the map does not have the property set. Our application does have custom system properties loading: the main() method loads a properties file and calls into System.setProperties(). My first instinct was to check the static initialization order, and to ensure the controller class with the main method does not call into log4j (directly or indirectly) before setting the properties just in case this was interfering with log4j's own initialization. Even removing all vestiges of log4j from the initialization logic, this error condition still occurs.

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• Misaligned Pointer Performance

  - by Elite Mx

  Aren't misaligned pointers (in the BEST possible case) supposed to slow down performance and in the worst case crash your program (assuming the compiler was nice enough to compile your invalid c program). Well, the following code doesn't seem to have any performance differences between the aligned and misaligned versions. Why is that? /* brutality.c */ #ifdef BRUTALITY xs = (unsigned long *) ((unsigned char *) xs + 1); #endif ... /* main.c */ #include <stdio.h> #include <stdlib.h> #define size_t_max ((size_t)-1) #define max_count(var) (size_t_max / (sizeof var)) int main(int argc, char *argv[]) { unsigned long sum, *xs, *itr, *xs_end; size_t element_count = max_count(*xs) >> 4; xs = malloc(element_count * (sizeof *xs)); if(!xs) exit(1); xs_end = xs + element_count - 1; sum = 0; for(itr = xs; itr < xs_end; itr++) *itr = 0; #include "brutality.c" itr = xs; while(itr < xs_end) sum += *itr++; printf("%lu\n", sum); /* we could free the malloc-ed memory here */ /* but we are almost done */ exit(0); } Compiled and tested on two separate machines using gcc -pedantic -Wall -O0 -std=c99 main.c for i in {0..9}; do time ./a.out; done

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• Objective-measures of the expressiveness of programming languages [closed]

  - by Casebash

  I am very interested in the expressiveness of different languages. Everyone who has programmed in multiple languages knows that sometimes a language allows you to express concepts which you can't express in other languages. You can have all kinds of subjective discussion about this, but naturally it would be better to have an objective measure. There do actually exist objective measures. One is Turing-Completeness, which means that a language is capable of generating any output that could be generated by following a sequential set of steps. There are also other lesser levels of expressiveness such as Finite State Automata. Now, except for domain specific languages, pretty much all modern languages are Turing complete. It is therefore natural to ask the following question: Can we can define any other formal measures of expressiveness which are greater than Turing completeness? Now of course we can't define this by considering the output that a program can generate, as Turing machines can already produce the same output that any other program can. But there are definitely different levels in what concepts can be expressed - surely no-one would argue that assembly language is as powerful as a modern object oriented language like Python. You could use your assembly to write a Python interpreter, so clearly any accurate objective measure would have to exclude this possibility. This also causes a problem with trying to define the expressiveness using the minimum number of symbols. How exactly to do so is not clear and indeed appears extremely difficult, but we can't assume that just because we don't know how to solve a problem, that nobody know how to. It is also doesn't really make sense to demand a definition of expressiveness before answering the question - after all the whole point of this question is to obtain such a definition. I think that my explanation will be clear enough for anyone with a strong theoretical background in computer science to understand what I am looking for. If you do have such a background and you disagree, please comment why, but if you don't thats probably why you don't understand the question.

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• PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/json.so' undefined symbol: ZVAL_DELREF

  - by crmpicco

  I have an issue where I am unable to use JSON, which would appear to be because of the following error. There is another thread on this forum this touches on a similar issue, but it's not quite the same. I am using CentOS 5.6 and have the following pear packages installed: [crmpicco@eq-www-php53 ~]$ pear list PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/json.so' - /usr/lib64/php/modules/json.so: undefined symbol: ZVAL_DELREF in Unknown on line 0 Installed packages, channel pear.php.net: ========================================= Package Version State Archive_Tar 1.3.7 stable Auth_SASL 1.0.2 stable Console_Getopt 1.3.1 stable Image_Barcode 1.1.2 stable Mail 1.1.14 stable Net_SMTP 1.2.10 stable Net_Socket 1.0.8 stable PEAR 1.9.4 stable Structures_Graph 1.0.4 stable XML_RPC 1.5.4 stable XML_Util 1.2.1 stable json 1.2.1 stable and have the following PHP packages installed: [crmpicco@eq-www-php53 ~]$ yum list installed | grep php php.x86_64 5.3.10-1.w5 installed php-cli.x86_64 5.3.10-1.w5 installed php-common.x86_64 5.3.10-1.w5 installed php-devel.x86_64 5.3.10-1.w5 installed php-gd.x86_64 5.3.10-1.w5 installed php-ldap.x86_64 5.3.10-1.w5 installed php-mcrypt.x86_64 5.3.10-1.w5 installed php-mysql.x86_64 5.3.10-1.w5 installed php-pdo.x86_64 5.3.10-1.w5 installed php-pear.noarch 1:1.9.4-1.w5 installed php-pear-Net-Socket.noarch 1.0.8-1.el5.centos installed php-soap.x86_64 5.3.10-1.w5 installed php-xml.x86_64 5.3.10-1.w5 installed The error: [crmpicco@eq-www-php53 ~]$ php -v PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/json.so' - /usr/lib64/php/modules/json.so: undefined symbol: ZVAL_DELREF in Unknown on line 0 PHP 5.3.10 (cli) (built: Feb 2 2012 23:23:12) Copyright (c) 1997-2012 The PHP Group Zend Engine v2.3.0, Copyright (c) 1998-2012 Zend Technologies My repolist reads as: [crmpicco@eq-www-php53 ~]$ yum repolist Loaded plugins: changelog, fastestmirror Excluding Packages in global exclude list Finished repo id repo name status base CentOS-5 - Base 3,548+43 epel Extra Packages for Enterprise Linux 5 - x86_64 6,815+156 extras CentOS-5 - Extras 245+23 rpmforge Red Hat Enterprise 5 - RPMforge.net - dag 11,016+67 updates CentOS-5 - Updates 233 webtatic Webtatic Repository 5 - x86_64 211+183 repolist: 22,068 I am getting HTTP 500 errors everywhere that I use JSON so my application is non functional right now.

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