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  • Where is /dev/dsp or /dev/audio?

    - by YumYumYum
    I have to apply sudo chmod a+r /dev/dsp or /dev/audio but in my Ubuntu 12.10 i do not have such. Where is then the PCM sound file for ssh? chmod: cannot access `/dev/dsp': No such file or directory chmod: cannot access `/dev/audio': No such file or directory Follow up: http://superuser.com/questions/244173/missing-dev-dsp-under-ubuntu I want to stream the sound output and input. So that i can capture any audio in/out to a file for recording.

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  • Attunity Oracle CDC Solution for SSIS - Beta

    We in no way work for Attunity but we were asked to test drive a beta version of their Oracle CDC solution for SSIS.  Everybody should know that moving more data than you need to takes too much time and uses resources that may better be employed doing something else.  Change data Capture is a technology that is designed to help you identify only the data that has had something done to it and you can therefore move only what is needed.  Microsoft have implemented this exact functionality into SQL server 2008 and I really like it there.  Attunity though are doing it on Oracle. DISCLAIMER: This is a BETA release and some of the parts are a bit ugly/difficult to work with.  The idea though is definitely right and the product once working does exactly what it says on the tin.  They have always been helpful to me when I have had a problem with the product and if that continues then beta testing pain should be eased somewhat. In due course I am going to be doing some videos around me using the product.  If you use Oracle and SSIS then give it a go. Here is their product description.   Attunity is a Microsoft SQL Server technology partner and the creator of the Microsoft Connectors for Oracle and Teradata, currently available in SQL Server 2008 Enterprise Edition. Attunity released a beta version of the Attunity Oracle-CDC for SSIS, a product that integrates continually changing Oracle data into SSIS, efficiently and in real-time. Attunity designed the product and integrated it into SSIS to create the simple creation of change data capture (CDC) solutions, accelerate implementation time, and reduce resources and costs. They also utilize log-based CDC so the solution has minimal impact on the Oracle source system. You can use the product to implement enterprise-class data replication, synchronization, and real-time business intelligence (BI) and data warehousing projects, quickly and efficiently, leveraging their existing SQL Server investments and resource skills. Attunity architected the product specifically for the Microsoft SSIS developer community and the product is available for both SQL Server 2005 and SQL Server 2008. It offers the following key capabilities: · Log-based, non-intrusive Oracle CDC · Full integration into SSIS and the Business Intelligence Developer Studio · Automatic generation of SSIS packages for CDC as well as full-loads of Oracle data · Filtering of Oracle tables and columns at the source · Monitoring and control of CDC processing Click to learn more and download the beta.

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  • ERROR running Bumblebee on 13.10

    - by paul
    I'm trying to get Bumblebee working again after an upgrade to Saucy. Running software with Optirun gives the following output: optirun nvidia-settings [ 45.697126] [ERROR]Cannot access secondary GPU - error: [XORG] (EE) Failed to load /usr/lib/xorg/modules/libglamoregl.so: /usr/lib/xorg/modules/libglamoregl.so: undefined symbol: _glapi_tls_Context [ 45.697179] [ERROR]Aborting because fallback start is disabled. Does anyone know how to fix this? Thanks! :)

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  • Is this possible to re-duplicate the hardware signal on Linux?

    - by Ted Wong
    Since that every things is a file on the UNIX system. If I have a hardware, for example, a mouse, move from left corner to right corner, it should produce some kinds of file to communicate with the system. So, if my assumption is correct, is this possible to do following things: Capture the raw data, which is about moving mouse cursor from left corner to right corner? Reduplicate the raw data, using a program, same producing speed, and data, in order to "redo" moving mouse cursor from left corner to right corner

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  • Why does LightDM only show a custom wallpaper on the login screen if I have selected one of the default wallpapers?

    - by Mauricio
    LightDM only changes wallpapers if I have selected one of the default wallpapers. If I choose another image from my pictures, LightDM shows the default wallpaper. Why is this happening, and how can I make LightDM show my wallpaper if it is not one of the defaults? As @doug said in his answer, it works if you click on the little + symbol in the appearance settings: after you do that, LightDM changes wallpapers.

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  • How to customize the ubuntu gnome 3 desktop?

    - by Francesco
    This is maybe a stupid question, but how can I choose my own background image on ubuntu gnome 3?? I click on Settings - Background - then I click on the current background preview to change it but I see only the defaults images! No + symbol to add or something. On the 'Pictures' tab there is nothing to select, I get an empty white page? I am running ubuntu gnome 13.04 3.9.6-030906-generic. Thanks!

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  • Unable to boot post upgade to 12.10 from 12.04 on a dial boot PC

    - by Prateek
    I have a dual boot PC with Win7 and Ubuntu. Last night I upgraded from 12.04 to 12.10 and since then I have not been able to boot and PC goes into grub rescue with error "File not found" I have tried the below steps set prefix=(hd0,msdos5)/boot/grub/i386-pc/ set root=(hd0,msdos5) insmod normal ( i get error symbol not found : 'grub_disk_dev_list'. when I try linux /boot/vmlinuz-3.2.0-32-generic root=/dev/sda5 ro (i get error - command not found 'linux' ) same for initrd I am not able to find out what sdXX to set also.

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  • C#/.NET Little Wonders: Comparer&lt;T&gt;.Default

    - by James Michael Hare
    I’ve been working with a wonderful team on a major release where I work, which has had the side-effect of occupying most of my spare time preparing, testing, and monitoring.  However, I do have this Little Wonder tidbit to offer today. Introduction The IComparable<T> interface is great for implementing a natural order for a data type.  It’s a very simple interface with a single method: 1: public interface IComparer<in T> 2: { 3: // Compare two instances of same type. 4: int Compare(T x, T y); 5: }  So what do we expect for the integer return value?  It’s a pseudo-relative measure of the ordering of x and y, which returns an integer value in much the same way C++ returns an integer result from the strcmp() c-style string comparison function: If x == y, returns 0. If x > y, returns > 0 (often +1, but not guaranteed) If x < y, returns < 0 (often –1, but not guaranteed) Notice that the comparison operator used to evaluate against zero should be the same comparison operator you’d use as the comparison operator between x and y.  That is, if you want to see if x > y you’d see if the result > 0. The Problem: Comparing With null Can Be Messy This gets tricky though when you have null arguments.  According to the MSDN, a null value should be considered equal to a null value, and a null value should be less than a non-null value.  So taking this into account we’d expect this instead: If x == y (or both null), return 0. If x > y (or y only is null), return > 0. If x < y (or x only is null), return < 0. But here’s the problem – if x is null, what happens when we attempt to call CompareTo() off of x? 1: // what happens if x is null? 2: x.CompareTo(y); It’s pretty obvious we’ll get a NullReferenceException here.  Now, we could guard against this before calling CompareTo(): 1: int result; 2:  3: // first check to see if lhs is null. 4: if (x == null) 5: { 6: // if lhs null, check rhs to decide on return value. 7: if (y == null) 8: { 9: result = 0; 10: } 11: else 12: { 13: result = -1; 14: } 15: } 16: else 17: { 18: // CompareTo() should handle a null y correctly and return > 0 if so. 19: result = x.CompareTo(y); 20: } Of course, we could shorten this with the ternary operator (?:), but even then it’s ugly repetitive code: 1: int result = (x == null) 2: ? ((y == null) ? 0 : -1) 3: : x.CompareTo(y); Fortunately, the null issues can be cleaned up by drafting in an external Comparer.  The Soltuion: Comparer<T>.Default You can always develop your own instance of IComparer<T> for the job of comparing two items of the same type.  The nice thing about a IComparer is its is independent of the things you are comparing, so this makes it great for comparing in an alternative order to the natural order of items, or when one or both of the items may be null. 1: public class NullableIntComparer : IComparer<int?> 2: { 3: public int Compare(int? x, int? y) 4: { 5: return (x == null) 6: ? ((y == null) ? 0 : -1) 7: : x.Value.CompareTo(y); 8: } 9: }  Now, if you want a custom sort -- especially on large-grained objects with different possible sort fields -- this is the best option you have.  But if you just want to take advantage of the natural ordering of the type, there is an easier way.  If the type you want to compare already implements IComparable<T> or if the type is System.Nullable<T> where T implements IComparable, there is a class in the System.Collections.Generic namespace called Comparer<T> which exposes a property called Default that will create a singleton that represents the default comparer for items of that type.  For example: 1: // compares integers 2: var intComparer = Comparer<int>.Default; 3:  4: // compares DateTime values 5: var dateTimeComparer = Comparer<DateTime>.Default; 6:  7: // compares nullable doubles using the null rules! 8: var nullableDoubleComparer = Comparer<double?>.Default;  This helps you avoid having to remember the messy null logic and makes it to compare objects where you don’t know if one or more of the values is null. This works especially well when creating say an IComparer<T> implementation for a large-grained class that may or may not contain a field.  For example, let’s say you want to create a sorting comparer for a stock open price, but if the market the stock is trading in hasn’t opened yet, the open price will be null.  We could handle this (assuming a reasonable Quote definition) like: 1: public class Quote 2: { 3: // the opening price of the symbol quoted 4: public double? Open { get; set; } 5:  6: // ticker symbol 7: public string Symbol { get; set; } 8:  9: // etc. 10: } 11:  12: public class OpenPriceQuoteComparer : IComparer<Quote> 13: { 14: // Compares two quotes by opening price 15: public int Compare(Quote x, Quote y) 16: { 17: return Comparer<double?>.Default.Compare(x.Open, y.Open); 18: } 19: } Summary Defining a custom comparer is often needed for non-natural ordering or defining alternative orderings, but when you just want to compare two items that are IComparable<T> and account for null behavior, you can use the Comparer<T>.Default comparer generator and you’ll never have to worry about correct null value sorting again.     Technorati Tags: C#,.NET,Little Wonders,BlackRabbitCoder,IComparable,Comparer

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  • Capturing index operations using a DDL trigger

    - by AaronBertrand
    Today on twitter the following question came up on the #sqlhelp hash tag, from DaveH0ward : Is there a DMV that can tell me the last time an index was rebuilt? SQL 2008 My initial response: I don't believe so, you'd have to be monitoring for that ... perhaps a DDL trigger capturing ALTER_INDEX? Then I remembered that the default trace in SQL Server ( as long as it is enabled ) will capture these events. My follow-up response: You can get it from the default trace, blog post forthcoming So here is...(read more)

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  • IrrKlang with Ogre

    - by Vinnie
    I'm trying to set up sound in my Ogre3D project. I have installed irrKlang 1.4.0 and added it's include and lib directories to my projects VC++ Include and Library directories, but I'm still getting a Linker error when I attempt to build. Any suggestions? (Error 4007 error LNK2019: unresolved external symbol "__declspec(dllimport) class irrklang::ISoundEngine * __cdecl irrklang::createIrrKlangDevice(enum irrklang::E_SOUND_OUTPUT_DRIVER,int,char const *,char const *)" (_imp?createIrrKlangDevice@irrklang@@YAPAVISoundEngine@1@W4E_SOUND_OUTPUT_DRIVER@1@HPBD1@Z) referenced in function "public: __thiscall SoundManager::SoundManager(void)" (??0SoundManager@@QAE@XZ)

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  • JavaOne 2012 - Java Generics

    - by Sharon Zakhour
    At JavaOne 2012, Venkat Subramaniam of Agile Developer, Inc, presented a conference session titled "The Good, The Bad, and the Ugly of Java Generics." Dr Subramaniam discussed the use of generics, what to watch out for when using generics, and best practices. To learn more about working with generics, see the Generics trail in the Java Tutorials. The trail was recently expanded and coverage added for the following topics: Generics, Inheritance, and Subtypes Guidelines for Wildcard Use Restrictions on Generics Wildcard Capture and Helper Methods Effects of Type Erasure and Bridge Methods

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  • Microsoft dévoile les grandes lignes du futur Internet Explorer et lance status.modern.ie, un portail web pour suivre le développement du navigateur

    Microsoft dévoile les grandes lignes du futur Internet Explorer et lance status.modern.ie un portail web pour suivre le développement du navigateurQuelques mois seulement après la sortie officielle d'Internet Explorer 11, Microsoft planche déjà sur la prochaine mouture du navigateur et dévoile certaines fonctionnalités qui seront supportées par le navigateur.Parmi les fonctionnalités annoncées : Web Audio API, Media Capture, Promises (ES6) et HTTP/2. Toutefois, l'éditeur explique que cette liste...

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  • Should UTF-16 be considered harmful?

    - by Artyom
    I'm going to ask what is probably quite a controversial question: "Should one of the most popular encodings, UTF-16, be considered harmful?" Why do I ask this question? How many programmers are aware of the fact that UTF-16 is actually a variable length encoding? By this I mean that there are code points that, represented as surrogate pairs, take more than one element. I know; lots of applications, frameworks and APIs use UTF-16, such as Java's String, C#'s String, Win32 APIs, Qt GUI libraries, the ICU Unicode library, etc. However, with all of that, there are lots of basic bugs in the processing of characters out of BMP (characters that should be encoded using two UTF-16 elements). For example, try to edit one of these characters: 𝄞 (U+1D11E) MUSICAL SYMBOL G CLEF 𝕥 (U+1D565) MATHEMATICAL DOUBLE-STRUCK SMALL T 𝟶 (U+1D7F6) MATHEMATICAL MONOSPACE DIGIT ZERO 𠂊 (U+2008A) Han Character You may miss some, depending on what fonts you have installed. These characters are all outside of the BMP (Basic Multilingual Plane). If you cannot see these characters, you can also try looking at them in the Unicode Character reference. For example, try to create file names in Windows that include these characters; try to delete these characters with a "backspace" to see how they behave in different applications that use UTF-16. I did some tests and the results are quite bad: Opera has problem with editing them (delete required 2 presses on backspace) Notepad can't deal with them correctly (delete required 2 presses on backspace) File names editing in Window dialogs in broken (delete required 2 presses on backspace) All QT3 applications can't deal with them - show two empty squares instead of one symbol. Python encodes such characters incorrectly when used directly u'X'!=unicode('X','utf-16') on some platforms when X in character outside of BMP. Python 2.5 unicodedata fails to get properties on such characters when python compiled with UTF-16 Unicode strings. StackOverflow seems to remove these characters from the text if edited directly in as Unicode characters (these characters are shown using HTML Unicode escapes). WinForms TextBox may generate invalid string when limited with MaxLength. It seems that such bugs are extremely easy to find in many applications that use UTF-16. So... Do you think that UTF-16 should be considered harmful?

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  • gstreamer pulseaudio echo cancellation

    - by user3618055
    I'm implementing a voip application using gstreamer, i use the example of the rtp in the plugin-good! i want to implement echo cancellation, i couldn't use the speex echo canceller with gstreamer because the input and the output are not in the same process. So, i want to use pulse audio to make echo cancellation? can any one help me how to deal with? the sender voice is pipeline = gst_pipeline_new (NULL); g_assert (pipeline); /* the audio capture and format conversion */ audiosrc = gst_element_factory_make (pulsesrc, "audiosrc"); g_assert (audiosrc); audioconv = gst_element_factory_make ("audioconvert", "audioconv"); g_assert (audioconv); audiores = gst_element_factory_make ("audioresample", "audiores"); g_assert (audiores); /* the encoding and payloading */ audioenc = gst_element_factory_make (AUDIO_ENC, "audioenc"); g_assert (audioenc); audiopay = gst_element_factory_make (AUDIO_PAY, "audiopay"); g_assert (audiopay); /* add capture and payloading to the pipeline and link */ gst_bin_add_many (GST_BIN (pipeline), audiosrc, audioconv, audiores, audioenc, audiopay, NULL); if (!gst_element_link_many (audiosrc, audioconv, audiores, audioenc, audiopay, NULL)) { g_error ("Failed to link audiosrc, audioconv, audioresample, " "audio encoder and audio payloader"); } and the receiver is : gst_bin_add_many (GST_BIN (pipeline), rtpsrc, rtcpsrc, rtcpsink, NULL); /* the depayloading and decoding */ audiodepay = gst_element_factory_make (AUDIO_DEPAY, "audiodepay"); g_assert (audiodepay); audiodec = gst_element_factory_make (AUDIO_DEC, "audiodec"); g_assert (audiodec); /* the audio playback and format conversion */ audioconv = gst_element_factory_make ("audioconvert", "audioconv"); g_assert (audioconv); audiores = gst_element_factory_make ("audioresample", "audiores"); g_assert (audiores); audiosink = gst_element_factory_make (pulsesink, "audiosink"); g_assert (audiosink); /* add depayloading and playback to the pipeline and link */ gst_bin_add_many (GST_BIN (pipeline), audiodepay, audiodec, audioconv, audiores, audiosink, NULL); res = gst_element_link_many (audiodepay, audiodec, audioconv, audiores, audiosink, NULL); g_assert (res == TRUE); i tried to change gstreamer proprietes to pulseaudio server in input and output and i used "pactl load-module module-echo-cancel aec_method=adrian" but i still listen to echo!! any one could help please thanks!!

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  • Why is Evince not displaying application fonts/text for me?

    - by Philippe Fenderson
    Any time I use Evince, it just shows boxes where all the text should be. Instead, it uses the box symbol which I know stands for not being able to find a character. This problem occurs on every menu, and makes it impossible to tell what's going on in any part of the application. I've tried Googling for this problem, but my -fu is weak or it's hard to search for. I'm pretty tech-literate, and I'm running a fairly stock 10.10 install with GNOME.

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  • Have you used the ExecutionValue and ExecValueVariable properties?

    The ExecutionValue execution value property and it’s friend ExecValueVariable are a much undervalued feature of SSIS, and many people I talk to are not even aware of their existence, so I thought I’d try and raise their profile a bit. The ExecutionValue property is defined on the base object Task, so all tasks have it available, but it is up to the task developer to do something useful with it. The basic idea behind it is that it allows the task to return something useful and interesting about what it has performed, in addition to the standard success or failure result. The best example perhaps is the Execute SQL Task which uses the ExecutionValue property to return the number of rows affected by the SQL statement(s). This is a very useful feature, something people often want to capture into a variable, and start using the result set options to do. Unfortunately we cannot read the value of a task property at runtime from within a SSIS package, so the ExecutionValue property on its own is a bit of a let down, but enter the ExecValueVariable and we have the perfect marriage. The ExecValueVariable is another property exposed through the task (TaskHost), which lets us select a SSIS package variable. What happens now is that when the task sets the ExecutionValue, the interesting value is copied into the variable we set on the ExecValueVariable property, and a variable is something we can access and do something with. So put simply if the ExecutionValue property value is of interest, make sure you create yourself a package variable and set the name as the ExecValueVariable. Have  look at the 3 step guide below: 1 Configure your task as normal, for example the Execute SQL Task, which here calls a stored procedure to do some updates. 2 Create variable of a suitable type to match the ExecutionValue, an integer is used to match the result we want to capture, the number of rows. 3 Set the ExecValueVariable for the task, just select the variable we created in step 2. You need to do this in Properties grid for the task (Short-cut key, select the task and press F4) Now when we execute the sample task above, our variable UpdateQueueRowCount will get the number of rows we updated in our Execute SQL Task. I’ve tried to collate a list of tasks that return something useful via the ExecutionValue and ExecValueVariable mechanism, but the documentation isn’t always great. Task ExecutionValue Description Execute SQL Task Returns the number of rows affected by the SQL statement or statements. File System Task Returns the number of successful operations performed by the task. File Watcher Task Returns the full path of the file found Transfer Error Messages Task Returns the number of error messages that have been transferred Transfer Jobs Task Returns the number of jobs that are transferred Transfer Logins Task Returns the number of logins transferred Transfer Master Stored Procedures Task Returns the number of stored procedures transferred Transfer SQL Server Objects Task Returns the number of objects transferred WMI Data Reader Task Returns an object that contains the results of the task. Not exactly clear, but I assume it depends on the WMI query used.

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  • Oracle GoldenGate: Knowledge Document Series Post #2

    - by Doug Reid
    0 false 18 pt 18 pt 0 0 false false false /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} 0 false 18 pt 18 pt 0 0 false false false /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} For our second post in this series the team would like to highlight the knowledge document “How-To: Oracle GoldenGate – Heartbeat Process to Monitor Lag and Performance”. This knowledge document outlines a procedure to reliably measure lag between source and target systems through the use of 'heartbeat' tables. The basic idea is to have a table on the source system that gets updated at a predetermined interval. In your capture processes you would capture the update from the heartbeat table. Using tokens you would add some additional information to the heartbeat record to be able to tell which extract process was capturing the update. This additional information would be used downstream to calculate the real lag time between the source and target systems for a given extract and by checking the last update time on the heartbeat at the target you could also determine if data has stopped flowing between the source and target.  Click here to view the document

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  • Install Dropbox in Xubuntu 11.10

    - by user34648
    I figured there might be a problem installing Dropbox using the .deb file from the website since XFCE doesn't use Nautilus. Some tutorials said that you have to install Nautilus first which I did. But when I installed Dropbox there weren't any problems and it even shows a symbol in the tray without me having to add anything. What I want to know is if installing Nautilus was necessary or not and which file manager I'm using now, Thunar or Nautilus?

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  • Debugging HLSL for Windows 8 application [migrated]

    - by Shervanator
    i'm currently in the process of creating a Windows 8 applicaiton using SharpDX (the managed c# directx wrapper). However I have ran into problems with one of my shaders and I want to know if its possible to debug such applications. PIX doesn't seem to work of directX apps as the executable does not like opening directly, and the new visual studio graphics debugging toolkit in VS2012 always states "unable to start the experiment" when I try to capture any information about my session. Thanks!

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  • import mini DV films from Samsung digital cam VP-D353 [USB]

    - by bobo
    I tried to import mini DV films from my old video camera VP-D353 and it's not reconised by my lubuntu.( 12.04 ) I tried "DVGRAB" which should work but it doesn't. I Found this tutorial http://www.foscode.com/linux-minidv-usb-video-capture/ But it's just saying "waiting for dv" I don't really know what should I do now. Here what I've got for the camera when I write : sudo lsub Bus 002 Device 013: ID 04e8:120f Samsung Electronics Co., Ltd thanks

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  • How to unit test with lots of IO

    - by Eric
    I write Linux embedded software which closely integrates with hardware. My modules are such as : -CMOS video input with kernel driver (v4l2) -Hardware h264/mpeg4 encoders (texas instuments) -Audio Capture/Playback (alsa) -Network IO I'd like to have automated testing for those functionalities, such as integration testing. I am not sure how I can automate this process since most of the top level functionalities I face are IO bound. Sure, it is easy to test functions individually, but whole process checking means depending on tons of external dependencies only available at runtime.

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  • How granular should a command be in a CQ[R]S model?

    - by Aaronaught
    I'm considering a project to migrate part of our WCF-based SOA over to a service bus model (probably nServiceBus) and using some basic pub-sub to achieve Command-Query Separation. I'm not new to SOA, or even to service bus models, but I confess that until recently my concept of "separation" was limited to run-of-the-mill database mirroring and replication. Still, I'm attracted to the idea because it seems to provide all the benefits of an eventually-consistent system while sidestepping many of the obvious drawbacks (most notably the lack of proper transactional support). I've read a lot on the subject from Udi Dahan who is basically the guru on ESB architectures (at least in the Microsoft world), but one thing he says really puzzles me: As we get larger entities with more fields on them, we also get more actors working with those same entities, and the higher the likelihood that something will touch some attribute of them at any given time, increasing the number of concurrency conflicts. [...] A core element of CQRS is rethinking the design of the user interface to enable us to capture our users’ intent such that making a customer preferred is a different unit of work for the user than indicating that the customer has moved or that they’ve gotten married. Using an Excel-like UI for data changes doesn’t capture intent, as we saw above. -- Udi Dahan, Clarified CQRS From the perspective described in the quotation, it's hard to argue with that logic. But it seems to go against the grain with respect to SOAs. An SOA (and really services in general) are supposed to deal with coarse-grained messages so as to minimize network chatter - among many other benefits. I realize that network chatter is less of an issue when you've got highly-distributed systems with good message queuing and none of the baggage of RPC, but it doesn't seem wise to dismiss the issue entirely. Udi almost seems to be saying that every attribute change (i.e. field update) ought to be its own command, which is hard to imagine in the context of one user potentially updating hundreds or thousands of combined entities and attributes as it often is with a traditional web service. One batch update in SQL Server may take a fraction of a second given a good highly-parameterized query, table-valued parameter or bulk insert to a staging table; processing all of these updates one at a time is slow, slow, slow, and OLTP database hardware is the most expensive of all to scale up/out. Is there some way to reconcile these competing concerns? Am I thinking about it the wrong way? Does this problem have a well-known solution in the CQS/ESB world? If not, then how does one decide what the "right level" of granularity in a Command should be? Is there some "standard" one can use as a starting point - sort of like 3NF in databases - and only deviate when careful profiling suggests a potentially significant performance benefit? Or is this possibly one of those things that, despite several strong opinions being expressed by various experts, is really just a matter of opinion?

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  • PAL–Performance Analysis of Logs

    - by GavinPayneUK
    I was doing some research earlier this week on SQL Server related troubleshooting tools and was surprised I’d forgotten about Microsoft’s PAL tool – Performance Analysis of Logs. PAL is a free PowerShell UI based tool from Microsoft that creates a perfmon template which can then be used to capture counters most relevant to a high-level performance review PAL will them give for specific Microsoft server deployments, SQL Server being one of them.  Everyone knows what perfmon does, probably too...(read more)

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  • Using the @ in SQL Azure Connections

    - by BuckWoody
    The other day I was working with a client on an application they were changing to a hybrid architecture – some data on-premise and other data in SQL Azure and Windows Azure Blob storage. I had them make a couple of corrections - the first was that all communications to SQL Azure need to be encrypted. It’s a simple addition to the connection string, depending on the library you use. Which brought up another interesting point. They had been using something that looked like this, using the .NET provider: Server=tcp:[serverName].database.windows.net;Database=myDataBase; User ID=LoginName;Password=myPassword; Trusted_Connection=False;Encrypt=True; This includes most of the formatting needed for SQL Azure. It specifies TCP as the transport mechanism, the database name is included, Trusted_Connection is off, and encryption is on. But it needed one more change: Server=tcp:[serverName].database.windows.net;Database=myDataBase; User ID=[LoginName]@[serverName];Password=myPassword; Trusted_Connection=False;Encrypt=True; Notice the difference? It’s the User ID parameter. It includes the @ symbol and the name of the server – not the whole DNS name, just the server name itself. The developers were a bit surprised, since it had been working with the first format that just used the user name. Why did both work, and why is one better than the other? It has to do with the connection library you use. For most libraries, the user name is enough. But for some libraries (subject to change so I don’t list them here) the server name parameter isn’t sent in the way the load balancer understands, so you need to include the server name right in the login, so the system can parse it correctly. Keep in mind, the string limit for that is 128 characters – so take the @ symbol and the server name into consideration for user names. The user connection info is detailed here: http://msdn.microsoft.com/en-us/library/ee336268.aspx Upshot? Include the @servername on your connection string just to be safe. And plan for that extra space…  

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