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  • Super Joybox 5 HID 0925:8884 not recognized as joystick in Ubuntu 12.04 LTS

    - by Tim Evans
    Problem: When using the "Super JoyBox 5" 4 port playstation 2 to USB adapter, the device is not recognized as a joystick. there is no js0 created, but instead another input eventX and mouseX are created in /dev/input. When using the directional buttons (up down left right) on a Playstation 1 controller attached to the device, the mouse cursor moves to the top, bottom, left, and right edges of the screen respectively. Buttons are unresponsive. The joypads attached to the device cannot be used in any games or other programs. Attempted remedies: Creating a symlink from the eventX to js0 does not solve the problem. Addl Info: joydev is loaded and running peroperly according to LSMOD. evtest can be run on the created eventX (sudo evtest /dev/input/event14 in my case) and the buttons and axes all register inputs. Here is a paste of EVTEST's diagnostic and the first couple button events. [code] sudo evtest /dev/input/event14 Input driver version is 1.0.1 Input device ID: bus 0x3 vendor 0x925 product 0x8884 version 0x100 Input device name: "HID 0925:8884" Supported events: Event type 0 (EV_SYN) Event type 1 (EV_KEY) Event code 288 (BTN_TRIGGER) Event code 289 (BTN_THUMB) Event code 290 (BTN_THUMB2) Event code 291 (BTN_TOP) Event code 292 (BTN_TOP2) Event code 293 (BTN_PINKIE) Event code 294 (BTN_BASE) Event code 295 (BTN_BASE2) Event code 296 (BTN_BASE3) Event code 297 (BTN_BASE4) Event code 298 (BTN_BASE5) Event code 299 (BTN_BASE6) Event code 300 (?) Event code 301 (?) Event code 302 (?) Event code 303 (BTN_DEAD) Event code 304 (BTN_A) Event code 305 (BTN_B) Event code 306 (BTN_C) Event code 307 (BTN_X) Event code 308 (BTN_Y) Event code 309 (BTN_Z) Event code 310 (BTN_TL) Event code 311 (BTN_TR) Event code 312 (BTN_TL2) Event code 313 (BTN_TR2) Event code 314 (BTN_SELECT) Event code 315 (BTN_START) Event code 316 (BTN_MODE) Event code 317 (BTN_THUMBL) Event code 318 (BTN_THUMBR) Event code 319 (?) Event code 320 (BTN_TOOL_PEN) Event code 321 (BTN_TOOL_RUBBER) Event code 322 (BTN_TOOL_BRUSH) Event code 323 (BTN_TOOL_PENCIL) Event code 324 (BTN_TOOL_AIRBRUSH) Event code 325 (BTN_TOOL_FINGER) Event code 326 (BTN_TOOL_MOUSE) Event code 327 (BTN_TOOL_LENS) Event code 328 (?) Event code 329 (?) Event code 330 (BTN_TOUCH) Event code 331 (BTN_STYLUS) Event code 332 (BTN_STYLUS2) Event code 333 (BTN_TOOL_DOUBLETAP) Event code 334 (BTN_TOOL_TRIPLETAP) Event code 335 (BTN_TOOL_QUADTAP) Event type 3 (EV_ABS) Event code 0 (ABS_X) Value 127 Min 0 Max 255 Flat 15 Event code 1 (ABS_Y) Value 127 Min 0 Max 255 Flat 15 Event code 2 (ABS_Z) Value 127 Min 0 Max 255 Flat 15 Event code 3 (ABS_RX) Value 127 Min 0 Max 255 Flat 15 Event code 4 (ABS_RY) Value 127 Min 0 Max 255 Flat 15 Event code 5 (ABS_RZ) Value 127 Min 0 Max 255 Flat 15 Event code 6 (ABS_THROTTLE) Value 127 Min 0 Max 255 Flat 15 Event code 7 (ABS_RUDDER) Value 127 Min 0 Max 255 Flat 15 Event code 8 (ABS_WHEEL) Value 127 Min 0 Max 255 Flat 15 Event code 9 (ABS_GAS) Value 127 Min 0 Max 255 Flat 15 Event code 10 (ABS_BRAKE) Value 127 Min 0 Max 255 Flat 15 Event code 11 (?) Value 127 Min 0 Max 255 Flat 15 Event code 12 (?) Value 127 Min 0 Max 255 Flat 15 Event code 13 (?) Value 127 Min 0 Max 255 Flat 15 Event code 14 (?) Value 127 Min 0 Max 255 Flat 15 Event code 15 (?) Value 127 Min 0 Max 255 Flat 15 Event code 16 (ABS_HAT0X) Value 0 Min -1 Max 1 Event code 17 (ABS_HAT0Y) Value 0 Min -1 Max 1 Event code 18 (ABS_HAT1X) Value 0 Min -1 Max 1 Event code 19 (ABS_HAT1Y) Value 0 Min -1 Max 1 Event code 20 (ABS_HAT2X) Value 0 Min -1 Max 1 Event code 21 (ABS_HAT2Y) Value 0 Min -1 Max 1 Event code 22 (ABS_HAT3X) Value 0 Min -1 Max 1 Event code 23 (ABS_HAT3Y) Value 0 Min -1 Max 1 Event type 4 (EV_MSC) Event code 4 (MSC_SCAN) Testing ... (interrupt to exit) Event: time 1351223176.126127, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90001 Event: time 1351223176.126130, type 1 (EV_KEY), code 288 (BTN_TRIGGER), value 1 Event: time 1351223176.126166, -------------- SYN_REPORT ------------ Event: time 1351223178.238127, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90001 Event: time 1351223178.238130, type 1 (EV_KEY), code 288 (BTN_TRIGGER), value 0 Event: time 1351223178.238167, -------------- SYN_REPORT ------------ Event: time 1351223180.422127, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90002 Event: time 1351223180.422129, type 1 (EV_KEY), code 289 (BTN_THUMB), value 1 Event: time 1351223180.422163, -------------- SYN_REPORT ------------ Event: time 1351223181.558099, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90002 Event: time 1351223181.558102, type 1 (EV_KEY), code 289 (BTN_THUMB), value 0 Event: time 1351223181.558137, -------------- SYN_REPORT ------------ Event: time 1351223182.486137, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90003 Event: time 1351223182.486140, type 1 (EV_KEY), code 290 (BTN_THUMB2), value 1 Event: time 1351223182.486172, -------------- SYN_REPORT ------------ Event: time 1351223183.302130, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90003 Event: time 1351223183.302132, type 1 (EV_KEY), code 290 (BTN_THUMB2), value 0 Event: time 1351223183.302165, -------------- SYN_REPORT ------------ Event: time 1351223184.030133, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90004 Event: time 1351223184.030136, type 1 (EV_KEY), code 291 (BTN_TOP), value 1 Event: time 1351223184.030166, -------------- SYN_REPORT ------------ Event: time 1351223184.558135, type 4 (EV_MSC), code 4 (MSC_SCAN), value 90004 Event: time 1351223184.558138, type 1 (EV_KEY), code 291 (BTN_TOP), value 0 Event: time 1351223184.558168, -------------- SYN_REPORT ------------ [/code] The directional buttons on the pad are being identified as HAT0Y and HAT0X axes, thats zero, not the letter O. Aparently, this device used to work flawlessly on kernel 2.4.x systems, and even as late as ubunto 10.04. Perhaps the Joydev rules for identifying joypads has changed? Currently, this kind of bug is affecting a few different type of controller adapters, but since this is the one that i PERSONALLY have (and has been driving me my own special brand of crazy), its the one im documenting. What i think should be happening instead: The device should be registering js0 through js3, one for each port, or JS0 that will handle all of the connected devices with different numbered axes for each connected joypad. Either way, it should work as a joystick and stop controlling the mouse cursor. Please help!

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  • In Javascript event handling, why "return false" or "event.preventDefault()" and "stopping the event

    - by Jian Lin
    It is said that when we handle a "click event", returning false or calling event.preventDefault() makes a difference, in which the difference is that preventDefault will only prevent the default event action to occur, i.e. a page redirect on a link click, a form submission, etc. and return false will also stop the event flow. Does that mean, if the click event is registered several times for several actions, using $('#clickme').click(function() { … }) returning false will stop the other handlers from running? I am on a Mac now and so can only use Firefox and Chrome but not IE, which has a different event model, and tested it on FF and Chrome and all 3 handlers ran without any stopping…. so what is the real difference, or, is there a situation where "stopping the event flow" is not desirable? this is related to http://stackoverflow.com/questions/3042036/using-jquerys-animate-if-the-clicked-on-element-is-a-href-a and http://stackoverflow.com/questions/2017755/whats-the-difference-between-e-preventdefault-and-return-false

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  • Attached event triggering if event is same as current event

    - by Psytronic
    I have a button which start/stops a timer. When I click it, I remove the current event handler, and attach the opposite one. Ie, click "Stop", and the "Start" function is attached for the next click. However in IE (7), not sure about 8. The newly attached event is also triggering after the original function is finished: Lifeline in IE7: Button pushed -- "Stop" function begins -- "Stop" function removed -- "Start" function attached -- "Stop" function finishes -- "Start" function is called. I know it's to do with the attaching event bit, because If I remove it, the Start event doesn't fire. This seems a bit odd, as I have the same situation in the "Start" function, ie, "Start" removed, "Stop" called. But this doesn't seem to cause an infinite loop, thankfully. if(btn.attachEvent){ btn.detachEvent("onclick", stop); btn.attachEvent("onclick", start); }else if(btn.addEventListener){ btn.removeEventListener("click", stop, true); btn.addEventListener("click", start , true); } It all works fine in FF and Chrome. I have switched the order of attach/detach, just to see if it makes a difference, but it doesn't. Addendum Sorry, and no answers involving jQuery, Protoype et al. Its not something I want to integrate for this project.

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  • Query specific logs from event log using nxlog

    - by user170899
    Below is my nxlog configuration define ROOT C:\Program Files (x86)\nxlog Moduledir %ROOT%\modules CacheDir %ROOT%\data Pidfile %ROOT%\data\nxlog.pid SpoolDir %ROOT%\data LogFile %ROOT%\data\nxlog.log <Extension json> Module xm_json </Extension> <Input internal> Module im_internal </Input> <Input eventlog> Module im_msvistalog Query <QueryList>\ <Query Id="0">\ <Select Path="Security">*</Select>\ </Query>\ </QueryList> </Input> <Output out> Module om_tcp Host localhost Port 3515 Exec $EventReceivedTime = integer($EventReceivedTime) / 1000000; \ to_json(); </Output> <Route 1> Path eventlog, internal => out </Route> <Select Path="Security">*</Select>\ - * gets everything from the Security log, but my requirement is to get specific logs starting with EventId - 4663. How do i do this? Please help. Thanks.

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  • Call a function when "event.GetFrom(m_cpVoice)==S_OK" (ergo when event happens) [SAPI 5.1 and C++]

    - by Jesuskiewicz
    Hello, I'm doing a project with a 3D model, that speaks. So, I'm using SAPI 5.1, and I want to call a function asynchronously when there's a Viseme event (in order to play the animation related to). How could I do it? Thank you very much. Note: I use : hRes = m_cpVoice-Speak(L"All I want is to solve this problem", SPF_ASYNC , NULL); And I know the CspEvent, event.eEventId . All I want is how to call a function when Sapi event happens

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  • SQLAuthority News – Book Signing Event – SQLPASS 2011 Event Log

    - by pinaldave
    I have been dreaming of writing book for really long time, and I finally got the chance – in fact, two chances!  I recently wrote two books: SQL Programming Joes 2 Pros: Programming and Development for Microsoft SQL Server 2008 [Amazon] | [Flipkart] | [Kindle] and SQL Wait Stats Joes 2 Pros: SQL Performance Tuning Techniques Using Wait Statistics, Types & Queues [Amazon] | [Flipkart] | [Kindle].  I had a lot of fun writing these two books, even though sometimes I had to sacrifice some family time and time for other personal development to write the books. The good side of writing book is that when the efforts put in writing books are recognize by books readers and kind organizations like expressor studio. Book Signing Event Book writing is a complex process.  Even after you spend months, maybe years, writing the material you still have to go through the editing and fact checking processes.  And, once the book is out there, there is no way to take back all the copies to change mistakes or add something you forgot.  Most of the time it is a one-way street. Book Signing Event Just like every author, I had a dream that after the books were written, they would be loved by people and gain acceptance by an audience. My first book, SQL Programming Joes 2 Pros: Programming and Development for Microsoft SQL Server 2008, is extremely popular because it helps lots of people learn various fundamental topics. My second book covers beginning to learn SQL Server Wait Stats, which is a relatively new subject. This book has had very good acceptance in the community. Book Signing Event Helping my community is my primary focus, so I was happy to see this year’s SQLPASS tag line: ‘This is a Community.‘ At the event, the expressor studio guys came up with a very novel idea. They had previously used my books and they had found them very useful. They got 100 copies of the book and decided to give it away to community folks. They invited me and my co-author Rick Morelan to hold a book signing event. We did a book signing on Thursday between 1 pm and 2 pm. Book Signing Event This event was one of the best events for me. This was my first book signing event outside of India. I reached the book signing location around 20 minutes before the scheduled time and what I saw was a big line for the book signing event. I felt very honored looking at the crowd and all the people around the event location. I felt very humbled when I saw some of my very close friends standing in the line to get my signature. It was really heartwarming to see so many enthusiasts waiting for more than an hour to get my signature. While standing in line I had the chance to have a conversation with every single person who showed up for the signature. I made sure that I repeated every single name and wrote it in every book with my signature. There is saying that if we write a name once we will remember it forever. I want to remember all of you who saw me at the book signing. Your comments were wonderful, your feedback was amazing and you were all very supportive. Book Signing Event I have made a note of every conversation I had with all of you when I was signing the books. Once again, I just want to express my thanks for coming to my book signing event. The whole experience was very humbling. On the top of it, I want to thank the expressor studio people who made it possible, who organized the whole signing event. I am so thankful to them for facilitating the whole experience, which is going to be hard to beat by any future experience. My books Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL PASS, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, T SQL, Technology

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  • User is trying to leave! Set at-least confirm alert on browser(tab) close event!!

    - by kaushalparik27
    This is something that might be annoying or irritating for end user. Obviously, It's impossible to prevent end user from closing the/any browser. Just think of this if it becomes possible!!!. That will be a horrible web world where everytime you will be attacked by sites and they will not allow to close your browser until you confirm your shopping cart and do the payment. LOL:) You need to open the task manager and might have to kill the running browser exe processes.Anyways; Jokes apart, but I have one situation where I need to alert/confirm from the user in any anyway when they try to close the browser or change the url. Think of this: You are creating a single page intranet asp.net application where your employee can enter/select their TDS/Investment Declarations and you wish to at-least ALERT/CONFIRM them if they are attempting to:[1] Close the Browser[2] Close the Browser Tab[3] Attempt to go some other site by Changing the urlwithout completing/freezing their declaration.So, Finally requirement is clear. I need to alert/confirm the user what he is going to do on above bulleted events. I am going to use window.onbeforeunload event to set the javascript confirm alert box to appear.    <script language="JavaScript" type="text/javascript">        window.onbeforeunload = confirmExit;        function confirmExit() {            return "You are about to exit the system before freezing your declaration! If you leave now and never return to freeze your declaration; then they will not go into effect and you may lose tax deduction, Are you sure you want to leave now?";        }    </script>See! you are halfway done!. So, every time browser unloads the page, above confirm alert causes to appear on front of user like below:By saying here "every time browser unloads the page"; I mean to say that whenever page loads or postback happens the browser onbeforeunload event will be executed. So, event a button submit or a link submit which causes page to postback would tend to execute the browser onbeforeunload event to fire!So, now the hurdle is how can we prevent the alert "Not to show when page is being postback" via any button/link submit? Answer is JQuery :)Idea is, you just need to set the script reference src to jQuery library and Set the window.onbeforeunload event to null when any input/link causes a page to postback.Below will be the complete code:<head runat="server">    <title></title>    <script src="jquery.min.js" type="text/javascript"></script>    <script language="JavaScript" type="text/javascript">        window.onbeforeunload = confirmExit;        function confirmExit() {            return "You are about to exit the system before freezing your declaration! If you leave now and never return to freeze your declaration; then they will not go into effect and you may lose tax deduction, Are you sure you want to leave now?";        }        $(function() {            $("a").click(function() {                window.onbeforeunload = null;            });            $("input").click(function() {                window.onbeforeunload = null;            });        });    </script></head><body>    <form id="form1" runat="server">    <div></div>    </form></body></html>So, By this post I have tried to set the confirm alert if user try to close the browser/tab or try leave the site by changing the url. I have attached a working example with this post here. I hope someone might find it helpful.

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  • wxPython - Running built in event prior to custom bound event

    - by jhaukur
    I'm trying to figure out how I can specify that the mouse_down event in wxPython (StyledTextCtrl) is first handled by the built in event listener, which changes the caret position, and then handled by my own custom event handler. To bind the custom event handler I use wx.EVT_LEFT_DOWN(self.styCtrl, self.OnMouseClick) def OnMouseClick(self, evt): evt.Skip() foo() I want the built in event handler to fire and complete prior to foo().

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  • Strengthening code with possibly useless exception handling

    - by rdurand
    Is it a good practice to implement useless exception handling, just in case another part of the code is not coded correctly? Basic example A simple one, so I don't loose everybody :). Let's say I'm writing an app that will display a person's information (name, address, etc.), the data being extracted from a database. Let's say I'm the one coding the UI part, and someone else is writing the DB query code. Now imagine that the specifications of your app say that if the person's information is incomplete (let's say, the name is missing in the database), the person coding the query should handle this by returning "NA" for the missing field. What if the query is poorly coded and doesn't handle this case? What if the guy who wrote the query handles you an incomplete result, and when you try to display the informations, everything crashes, because your code isn't prepared to display empty stuff? This example is very basic. I believe most of you will say "it's not your problem, you're not responsible for this crash". But, it's still your part of the code which is crashing. Another example Let's say now I'm the one writing the query. The specifications don't say the same as above, but that the guy writing the "insert" query should make sure all the fields are complete when adding a person to the database to avoid inserting incomplete information. Should I protect my "select" query to make sure I give the UI guy complete informations? The questions What if the specifications don't explicitly say "this guy is the one in charge of handling this situation"? What if a third person implements another query (similar to the first one, but on another DB) and uses your UI code to display it, but doesn't handle this case in his code? Should I do what's necessary to prevent a possible crash, even if I'm not the one supposed to handle the bad case? I'm not looking for an answer like "(s)he's the one responsible for the crash", as I'm not solving a conflict here, I'd like to know, should I protect my code against situations it's not my responsibility to handle? Here, a simple "if empty do something" would suffice. In general, this question tackles redundant exception handling. I'm asking it because when I work alone on a project, I may code 2-3 times a similar exception handling in successive functions, "just in case" I did something wrong and let a bad case come through.

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  • Error Handling without Exceptions

    - by James
    While searching SO for approaches to error handling related to business rule validation , all I encounter are examples of structured exception handling. MSDN and many other reputable development resources are very clear that exceptions are not to be used to handle routine error cases. They are only to be used for exceptional circumstances and unexpected errors that may occur from improper use by the programmer (but not the user.) In many cases, user errors such as fields that are left blank are common, and things which our program should expect, and therefore are not exceptional and not candidates for use of exceptions. QUOTE: Remember that the use of the term exception in programming has to do with the thinking that an exception should represent an exceptional condition. Exceptional conditions, by their very nature, do not normally occur; so your code should not throw exceptions as part of its everyday operations. Do not throw exceptions to signal commonly occurring events. Consider using alternate methods to communicate to a caller the occurrence of those events and leave the exception throwing for when something truly out of the ordinary happens. For example, proper use: private void DoSomething(string requiredParameter) { if (requiredParameter == null) throw new ArgumentExpcetion("requiredParameter cannot be null"); // Remainder of method body... } Improper use: // Renames item to a name supplied by the user. Name must begin with an "F". public void RenameItem(string newName) { // Items must have names that begin with "F" if (!newName.StartsWith("F")) throw new RenameException("New name must begin with /"F/""); // Remainder of method body... } In the above case, according to best practices, it would have been better to pass the error up to the UI without involving/requiring .NET's exception handling mechanisms. Using the same example above, suppose one were to need to enforce a set of naming rules against items. What approach would be best? Having the method return a enumerated result? RenameResult.Success, RenameResult.TooShort, RenameResult.TooLong, RenameResult.InvalidCharacters, etc. Using an event in a controller class to report to the UI class? The UI calls the controller's RenameItem method, and then handles an AfterRename event that the controller raises and that has rename status as part of the event args? The controlling class directly references and calls a method from the UI class that handles the error, e.g. ReportError(string text). Something else... ? Essentially, I want to know how to perform complex validation in classes that may not be the Form class itself, and pass the errors back to the Form class for display -- but I do not want to involve exception handling where it should not be used (even though it seems much easier!) Based on responses to the question, I feel that I'll have to state the problem in terms that are more concrete: UI = User Interface, BLL = Business Logic Layer (in this case, just a different class) User enters value within UI. UI reports value to BLL. BLL performs routine validation of the value. BLL discovers rule violation. BLL returns rule violation to UI. UI recieves return from BLL and reports error to user. Since it is routine for a user to enter invalid values, exceptions should not be used. What is the right way to do this without exceptions?

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  • how to re-enable default after doing event.preventDefault()

    - by Matt
    Hi, I know this exact question was asked here, but the answer didn't work for what I needed to do so I figured I'd give some example code and explain a bit... $(document).keypress( function (event) { // Pressing Up or Right: Advance to next video if (event.keyCode == 40 || event.keyCode == 39) { event.preventDefault(); $(".current").next().click(); } // Pressing Down or Left: Back to previous video else if (event.keyCode == 38 || event.keyCode == 37) { event.preventDefault(); $(".current").prev().click(); } } ); It basically disables the arrow keys to use them for something else, but doing: $(document).keypress(function () { }); doesn't enable the default function again... I need it to scroll the page without having to create a scroll function for it... Any ideas? Thanks, Matt

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  • Implement Exception Handling in ASP.NET C# Project

    - by Shrewd Demon
    hi, I have an application that has many tiers. as in, i have... Presentation Layer (PL) - contains all the html My Codes Layer (CL) - has all my code Entity Layer (EL) - has all the container entities Business Logic Layer (BLL) - has the necessary business logic Data Logic Layer (DLL) - any logic against data Data Access Layer (DAL) - one that accesses data from the database Now i want to provide error handling in my DLL since it is responsible for executing statement like ExecureScalar and all.... And i am confused as to how to go about it...i mean do i catch the error in the DLL and throw it back to the BLL and from there throw it back to my code or what.... can any one please help me how do i implement a clean and easy error handling techinque help you be really appreciated. Thank you.

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  • Event sourcing: Write event before or after updating the model

    - by Magnus
    I'm reasoning about event sourcing and often I arrive at a chicken and egg problem. Would be grateful for some hints on how to reason around this. If I execute all I/O-bound processing async (ie writing to the event log) then how do I handle, or sometimes even detect, failures? I'm using Akka Actors so processing is sequential for each event/message. I do not have any database at this time, instead I would persist all the events in an event log and then keep an aggregated state of all the events in a model stored in memory. Queries are all against this model, you can consider it to be a cache. Example Creating a new user: Validate that the user does not exist in model Persist event to journal Update model (in memory) If step 3 breaks I still have persisted my event so I can replay it at a later date. If step 2 breaks I can handle that as well gracefully. This is fine, but since step 2 is I/O-bound I figured that I should do I/O in a separate actor to free up the first actor for queries: Updating a user while allowing queries (A0 = Front end/GUI actor, A1 = Processor Actor, A2 = IO-actor, E = event bus). (A0-E-A1) Event is published to update user 'U1'. Validate that the user 'U1' exists in model (A1-A2) Persist event to journal (separate actor) (A0-E-A1-A0) Query for user 'U1' profile (A2-A1) Event is now persisted continue to update model (A0-E-A1-A0) Query for user 'U1' profile (now returns fresh data) This is appealing since queries can be processed while I/O-is churning along at it's own pace. But now I can cause myself all kinds of problems where I could have two incompatible commands (delete and then update) be persisted to the event log and crash on me when replayed up at a later date, since I do the validation before persisting the event and then update the model. My aim is to have a simple reasoning around my model (since Actor processes messages sequentially single threaded) but not be waiting for I/O-bound updates when Querying. I get the feeling I'm modeling a database which in itself is might be a problem. If things are unclear please write a comment.

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  • Backward compatibility with event-sourcing

    - by Tomas Jansson
    How do you stay backward compatible with event-sourcing? Let say you release a version that has one kind of event, let call it X. You know how to handle that event in all the systems that extracts the events from the event source. In a later release you make a change to event X or delete it, how do you stay backward compatible with that? To have a fully functional system you need to be able to handle the old event as the same time as you need to handle the updated version. Or if you delete that event type, then you will be stuck with code that is only there to handle legacy events which in my head can be a little bit messy in the long run.

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  • Best exception handling practices or recommendations?

    - by user828584
    I think the two main problems with my programs are my code structure/organization and my error handling. I'm reading Code Complete 2, but I need something to read for working with potential problems. For example, on a website, if something can only happen if the user tampers with data via javascript, do you write for that? Also, when do you not catch errors? When you write a class that expects a string and an int as input, and they aren't a string and int, do you check for that, or do you let it bubble up to the calling method that passed incorrect parameters? I know this is a broad topic that can't be answered in a single answer here, so what I'm looking for is a book or resource that's commonly accepted as teaching proper exception handling practice.

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  • Handling Errors In PHP When Using MVC

    - by James Jeffery
    I've been using Codeigniter a lot recently, but one thing that gets on my nerves is handling errors and displaying them to the user. I've never been good at handling errors without it getting messy. My main concern is when returning errors to the user. Is it good practice to use exceptions and throw/catch exceptions rather than returning 0 or 1 from functions and then using if/else to handle the errors. Thus, making it easier to inform the user about the issue. I tend to go away from exceptions. My Java tutor at university some years ago told me "exceptions shouldn't be used in production code it's more for debugging". I get the feeling he was lying. But, an example, I have code that adds a user to a database. During the process more than 1 thing could go wrong, such as a database issue, a duplicate entry, a server issue, etc. When an issue happens during registration the user needs to know about it. What's the best way to handle errors in PHP, keeping in mind that I'm using an MVC framework.

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  • Cutom event dispatchment location

    - by Martino Wullems
    Hello, I've been looking into custom event (listeners) for quite some time, but never succeeded in making one. There are so many different mehods, extending the Event class, but also Extending the EventDispatcher class, very confusing! I want to settle with this once and for all and learn the appriopate technique. package{ import flash.events.Event; public class CustomEvent extends Event{ public static const TEST:String = 'test'; //what exac is the purpose of the value in the string? public var data:Object; public function CustomEvent(type:String, bubbles:Boolean = false, cancelable:Boolean = false, data:Object = null):void { this.data = data; super(); } } } As far as I know a custom class where you set the requirements for the event to be dispatched has to be made: package { import flash.display.MovieClip; public class TestClass extends MovieClip { public function TestClass():void { if (ConditionForHoldToComplete == true) { dispatchEvent(new Event(CustomEvent.TEST)); } } } } I'm not sure if this is correct, but it should be something along the lines of this. Now What I want is something like a mouseevent, which can be applied to a target and does not require a specific class. It would have to work something like this: package com.op_pad._events{ import flash.events.MouseEvent; import flash.utils.Timer; import flash.events.TimerEvent; import flash.events.EventDispatcher; import flash.events.Event; public class HoldEvent extends Event { public static const HOLD_COMPLETE:String = "hold completed"; var timer:Timer; public function SpriteEvent(type:String, bubbles:Boolean=true, cancelable:Boolean=false) { super( type, bubbles, cancelable ); timer = new Timer(1000, 1); //somehow find the target where is event is placed upon -> target.addEventlistener target.addEventListener(MouseEvent.MOUSE_DOWN, startTimer); target.addEventListener(MouseEvent.MOUSE_UP, stopTimer); } public override function clone():Event { return new SpriteEvent(type, bubbles, cancelable); } public override function toString():String { return formatToString("MovieEvent", "type", "bubbles", "cancelable", "eventPhase"); } ////////////////////////////////// ///// c o n d i t i o n s ///// ////////////////////////////////// private function startTimer(e:MouseEvent):void { timer.start(); timer.addEventListener(TimerEvent.TIMER_COMPLETE, complete); } private function stopTimer(e:MouseEvent):void { timer.stop() } public function complete(e:TimerEvent):void { dispatchEvent(new HoldEvent(HoldEvent.HOLD_COMPLETE)); } } } This obviously won't work, but should give you an idea of what I want to achieve. This should be possible because mouseevent can be applied to about everything.The main problem is that I don't know where I should set the requirements for the event to be executed to be able to apply it to movieclips and sprites. Thanks in advance

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  • Option Trading: Getting the most out of the event session options

    - by extended_events
    You can control different aspects of how an event session behaves by setting the event session options as part of the CREATE EVENT SESSION DDL. The default settings for the event session options are designed to handle most of the common event collection situations so I generally recommend that you just use the defaults. Like everything in the real world though, there are going to be a handful of “special cases” that require something different. This post focuses on identifying the special cases and the correct use of the options to accommodate those cases. There is a reason it’s called Default The default session options specify a total event buffer size of 4 MB with a 30 second latency. Translating this into human terms; this means that our default behavior is that the system will start processing events from the event buffer when we reach about 1.3 MB of events or after 30 seconds, which ever comes first. Aside: What’s up with the 1.3 MB, I thought you said the buffer was 4 MB?The Extended Events engine takes the total buffer size specified by MAX_MEMORY (4MB by default) and divides it into 3 equally sized buffers. This is done so that a session can be publishing events to one buffer while other buffers are being processed. There are always at least three buffers; how to get more than three is covered later. Using this configuration, the Extended Events engine can “keep up” with most event sessions on standard workloads. Why is this? The fact is that most events are small, really small; on the order of a couple hundred bytes. Even when you start considering events that carry dynamically sized data (eg. binary, text, etc.) or adding actions that collect additional data, the total size of the event is still likely to be pretty small. This means that each buffer can likely hold thousands of events before it has to be processed. When the event buffers are finally processed there is an economy of scale achieved since most targets support bulk processing of the events so they are processed at the buffer level rather than the individual event level. When all this is working together it’s more likely that a full buffer will be processed and put back into the ready queue before the remaining buffers (remember, there are at least three) are full. I know what you’re going to say: “My server is exceptional! My workload is so massive it defies categorization!” OK, maybe you weren’t going to say that exactly, but you were probably thinking it. The point is that there are situations that won’t be covered by the Default, but that’s a good place to start and this post assumes you’ve started there so that you have something to look at in order to determine if you do have a special case that needs different settings. So let’s get to the special cases… What event just fired?! How about now?! Now?! If you believe the commercial adage from Heinz Ketchup (Heinz Slow Good Ketchup ad on You Tube), some things are worth the wait. This is not a belief held by most DBAs, particularly DBAs who are looking for an answer to a troubleshooting question fast. If you’re one of these anxious DBAs, or maybe just a Program Manager doing a demo, then 30 seconds might be longer than you’re comfortable waiting. If you find yourself in this situation then consider changing the MAX_DISPATCH_LATENCY option for your event session. This option will force the event buffers to be processed based on your time schedule. This option only makes sense for the asynchronous targets since those are the ones where we allow events to build up in the event buffer – if you’re using one of the synchronous targets this option isn’t relevant. Avoid forgotten events by increasing your memory Have you ever had one of those days where you keep forgetting things? That can happen in Extended Events too; we call it dropped events. In order to optimizes for server performance and help ensure that the Extended Events doesn’t block the server if to drop events that can’t be published to a buffer because the buffer is full. You can determine if events are being dropped from a session by querying the dm_xe_sessions DMV and looking at the dropped_event_count field. Aside: Should you care if you’re dropping events?Maybe not – think about why you’re collecting data in the first place and whether you’re really going to miss a few dropped events. For example, if you’re collecting query duration stats over thousands of executions of a query it won’t make a huge difference to miss a couple executions. Use your best judgment. If you find that your session is dropping events it means that the event buffer is not large enough to handle the volume of events that are being published. There are two ways to address this problem. First, you could collect fewer events – examine you session to see if you are over collecting. Do you need all the actions you’ve specified? Could you apply a predicate to be more specific about when you fire the event? Assuming the session is defined correctly, the next option is to change the MAX_MEMORY option to a larger number. Picking the right event buffer size might take some trial and error, but a good place to start is with the number of dropped events compared to the number you’ve collected. Aside: There are three different behaviors for dropping events that you specify using the EVENT_RETENTION_MODE option. The default is to allow single event loss and you should stick with this setting since it is the best choice for keeping the impact on server performance low.You’ll be tempted to use the setting to not lose any events (NO_EVENT_LOSS) – resist this urge since it can result in blocking on the server. If you’re worried that you’re losing events you should be increasing your event buffer memory as described in this section. Some events are too big to fail A less common reason for dropping an event is when an event is so large that it can’t fit into the event buffer. Even though most events are going to be small, you might find a condition that occasionally generates a very large event. You can determine if your session is dropping large events by looking at the dm_xe_sessions DMV once again, this time check the largest_event_dropped_size. If this value is larger than the size of your event buffer [remember, the size of your event buffer, by default, is max_memory / 3] then you need a large event buffer. To specify a large event buffer you set the MAX_EVENT_SIZE option to a value large enough to fit the largest event dropped based on data from the DMV. When you set this option the Extended Events engine will create two buffers of this size to accommodate these large events. As an added bonus (no extra charge) the large event buffer will also be used to store normal events in the cases where the normal event buffers are all full and waiting to be processed. (Note: This is just a side-effect, not the intended use. If you’re dropping many normal events then you should increase your normal event buffer size.) Partitioning: moving your events to a sub-division Earlier I alluded to the fact that you can configure your event session to use more than the standard three event buffers – this is called partitioning and is controlled by the MEMORY_PARTITION_MODE option. The result of setting this option is fairly easy to explain, but knowing when to use it is a bit more art than science. First the science… You can configure partitioning in three ways: None, Per NUMA Node & Per CPU. This specifies the location where sets of event buffers are created with fairly obvious implication. There are rules we follow for sub-dividing the total memory (specified by MAX_MEMORY) between all the event buffers that are specific to the mode used: None: 3 buffers (fixed)Node: 3 * number_of_nodesCPU: 2.5 * number_of_cpus Here are some examples of what this means for different Node/CPU counts: Configuration None Node CPU 2 CPUs, 1 Node 3 buffers 3 buffers 5 buffers 6 CPUs, 2 Node 3 buffers 6 buffers 15 buffers 40 CPUs, 5 Nodes 3 buffers 15 buffers 100 buffers   Aside: Buffer size on multi-processor computersAs the number of Nodes or CPUs increases, the size of the event buffer gets smaller because the total memory is sub-divided into more pieces. The defaults will hold up to this for a while since each buffer set is holding events only from the Node or CPU that it is associated with, but at some point the buffers will get too small and you’ll either see events being dropped or you’ll get an error when you create your session because you’re below the minimum buffer size. Increase the MAX_MEMORY setting to an appropriate number for the configuration. The most likely reason to start partitioning is going to be related to performance. If you notice that running an event session is impacting the performance of your server beyond a reasonably expected level [Yes, there is a reasonably expected level of work required to collect events.] then partitioning might be an answer. Before you partition you might want to check a few other things: Is your event retention set to NO_EVENT_LOSS and causing blocking? (I told you not to do this.) Consider changing your event loss mode or increasing memory. Are you over collecting and causing more work than necessary? Consider adding predicates to events or removing unnecessary events and actions from your session. Are you writing the file target to the same slow disk that you use for TempDB and your other high activity databases? <kidding> <not really> It’s always worth considering the end to end picture – if you’re writing events to a file you can be impacted by I/O, network; all the usual stuff. Assuming you’ve ruled out the obvious (and not so obvious) issues, there are performance conditions that will be addressed by partitioning. For example, it’s possible to have a successful event session (eg. no dropped events) but still see a performance impact because you have many CPUs all attempting to write to the same free buffer and having to wait in line to finish their work. This is a case where partitioning would relieve the contention between the different CPUs and likely reduce the performance impact cause by the event session. There is no DMV you can check to find these conditions – sorry – that’s where the art comes in. This is  largely a matter of experimentation. On the bright side you probably won’t need to to worry about this level of detail all that often. The performance impact of Extended Events is significantly lower than what you may be used to with SQL Trace. You will likely only care about the impact if you are trying to set up a long running event session that will be part of your everyday workload – sessions used for short term troubleshooting will likely fall into the “reasonably expected impact” category. Hey buddy – I think you forgot something OK, there are two options I didn’t cover: STARTUP_STATE & TRACK_CAUSALITY. If you want your event sessions to start automatically when the server starts, set the STARTUP_STATE option to ON. (Now there is only one option I didn’t cover.) I’m going to leave causality for another post since it’s not really related to session behavior, it’s more about event analysis. - Mike Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • Option Trading: Getting the most out of the event session options

    - by extended_events
    You can control different aspects of how an event session behaves by setting the event session options as part of the CREATE EVENT SESSION DDL. The default settings for the event session options are designed to handle most of the common event collection situations so I generally recommend that you just use the defaults. Like everything in the real world though, there are going to be a handful of “special cases” that require something different. This post focuses on identifying the special cases and the correct use of the options to accommodate those cases. There is a reason it’s called Default The default session options specify a total event buffer size of 4 MB with a 30 second latency. Translating this into human terms; this means that our default behavior is that the system will start processing events from the event buffer when we reach about 1.3 MB of events or after 30 seconds, which ever comes first. Aside: What’s up with the 1.3 MB, I thought you said the buffer was 4 MB?The Extended Events engine takes the total buffer size specified by MAX_MEMORY (4MB by default) and divides it into 3 equally sized buffers. This is done so that a session can be publishing events to one buffer while other buffers are being processed. There are always at least three buffers; how to get more than three is covered later. Using this configuration, the Extended Events engine can “keep up” with most event sessions on standard workloads. Why is this? The fact is that most events are small, really small; on the order of a couple hundred bytes. Even when you start considering events that carry dynamically sized data (eg. binary, text, etc.) or adding actions that collect additional data, the total size of the event is still likely to be pretty small. This means that each buffer can likely hold thousands of events before it has to be processed. When the event buffers are finally processed there is an economy of scale achieved since most targets support bulk processing of the events so they are processed at the buffer level rather than the individual event level. When all this is working together it’s more likely that a full buffer will be processed and put back into the ready queue before the remaining buffers (remember, there are at least three) are full. I know what you’re going to say: “My server is exceptional! My workload is so massive it defies categorization!” OK, maybe you weren’t going to say that exactly, but you were probably thinking it. The point is that there are situations that won’t be covered by the Default, but that’s a good place to start and this post assumes you’ve started there so that you have something to look at in order to determine if you do have a special case that needs different settings. So let’s get to the special cases… What event just fired?! How about now?! Now?! If you believe the commercial adage from Heinz Ketchup (Heinz Slow Good Ketchup ad on You Tube), some things are worth the wait. This is not a belief held by most DBAs, particularly DBAs who are looking for an answer to a troubleshooting question fast. If you’re one of these anxious DBAs, or maybe just a Program Manager doing a demo, then 30 seconds might be longer than you’re comfortable waiting. If you find yourself in this situation then consider changing the MAX_DISPATCH_LATENCY option for your event session. This option will force the event buffers to be processed based on your time schedule. This option only makes sense for the asynchronous targets since those are the ones where we allow events to build up in the event buffer – if you’re using one of the synchronous targets this option isn’t relevant. Avoid forgotten events by increasing your memory Have you ever had one of those days where you keep forgetting things? That can happen in Extended Events too; we call it dropped events. In order to optimizes for server performance and help ensure that the Extended Events doesn’t block the server if to drop events that can’t be published to a buffer because the buffer is full. You can determine if events are being dropped from a session by querying the dm_xe_sessions DMV and looking at the dropped_event_count field. Aside: Should you care if you’re dropping events?Maybe not – think about why you’re collecting data in the first place and whether you’re really going to miss a few dropped events. For example, if you’re collecting query duration stats over thousands of executions of a query it won’t make a huge difference to miss a couple executions. Use your best judgment. If you find that your session is dropping events it means that the event buffer is not large enough to handle the volume of events that are being published. There are two ways to address this problem. First, you could collect fewer events – examine you session to see if you are over collecting. Do you need all the actions you’ve specified? Could you apply a predicate to be more specific about when you fire the event? Assuming the session is defined correctly, the next option is to change the MAX_MEMORY option to a larger number. Picking the right event buffer size might take some trial and error, but a good place to start is with the number of dropped events compared to the number you’ve collected. Aside: There are three different behaviors for dropping events that you specify using the EVENT_RETENTION_MODE option. The default is to allow single event loss and you should stick with this setting since it is the best choice for keeping the impact on server performance low.You’ll be tempted to use the setting to not lose any events (NO_EVENT_LOSS) – resist this urge since it can result in blocking on the server. If you’re worried that you’re losing events you should be increasing your event buffer memory as described in this section. Some events are too big to fail A less common reason for dropping an event is when an event is so large that it can’t fit into the event buffer. Even though most events are going to be small, you might find a condition that occasionally generates a very large event. You can determine if your session is dropping large events by looking at the dm_xe_sessions DMV once again, this time check the largest_event_dropped_size. If this value is larger than the size of your event buffer [remember, the size of your event buffer, by default, is max_memory / 3] then you need a large event buffer. To specify a large event buffer you set the MAX_EVENT_SIZE option to a value large enough to fit the largest event dropped based on data from the DMV. When you set this option the Extended Events engine will create two buffers of this size to accommodate these large events. As an added bonus (no extra charge) the large event buffer will also be used to store normal events in the cases where the normal event buffers are all full and waiting to be processed. (Note: This is just a side-effect, not the intended use. If you’re dropping many normal events then you should increase your normal event buffer size.) Partitioning: moving your events to a sub-division Earlier I alluded to the fact that you can configure your event session to use more than the standard three event buffers – this is called partitioning and is controlled by the MEMORY_PARTITION_MODE option. The result of setting this option is fairly easy to explain, but knowing when to use it is a bit more art than science. First the science… You can configure partitioning in three ways: None, Per NUMA Node & Per CPU. This specifies the location where sets of event buffers are created with fairly obvious implication. There are rules we follow for sub-dividing the total memory (specified by MAX_MEMORY) between all the event buffers that are specific to the mode used: None: 3 buffers (fixed)Node: 3 * number_of_nodesCPU: 2.5 * number_of_cpus Here are some examples of what this means for different Node/CPU counts: Configuration None Node CPU 2 CPUs, 1 Node 3 buffers 3 buffers 5 buffers 6 CPUs, 2 Node 3 buffers 6 buffers 15 buffers 40 CPUs, 5 Nodes 3 buffers 15 buffers 100 buffers   Aside: Buffer size on multi-processor computersAs the number of Nodes or CPUs increases, the size of the event buffer gets smaller because the total memory is sub-divided into more pieces. The defaults will hold up to this for a while since each buffer set is holding events only from the Node or CPU that it is associated with, but at some point the buffers will get too small and you’ll either see events being dropped or you’ll get an error when you create your session because you’re below the minimum buffer size. Increase the MAX_MEMORY setting to an appropriate number for the configuration. The most likely reason to start partitioning is going to be related to performance. If you notice that running an event session is impacting the performance of your server beyond a reasonably expected level [Yes, there is a reasonably expected level of work required to collect events.] then partitioning might be an answer. Before you partition you might want to check a few other things: Is your event retention set to NO_EVENT_LOSS and causing blocking? (I told you not to do this.) Consider changing your event loss mode or increasing memory. Are you over collecting and causing more work than necessary? Consider adding predicates to events or removing unnecessary events and actions from your session. Are you writing the file target to the same slow disk that you use for TempDB and your other high activity databases? <kidding> <not really> It’s always worth considering the end to end picture – if you’re writing events to a file you can be impacted by I/O, network; all the usual stuff. Assuming you’ve ruled out the obvious (and not so obvious) issues, there are performance conditions that will be addressed by partitioning. For example, it’s possible to have a successful event session (eg. no dropped events) but still see a performance impact because you have many CPUs all attempting to write to the same free buffer and having to wait in line to finish their work. This is a case where partitioning would relieve the contention between the different CPUs and likely reduce the performance impact cause by the event session. There is no DMV you can check to find these conditions – sorry – that’s where the art comes in. This is  largely a matter of experimentation. On the bright side you probably won’t need to to worry about this level of detail all that often. The performance impact of Extended Events is significantly lower than what you may be used to with SQL Trace. You will likely only care about the impact if you are trying to set up a long running event session that will be part of your everyday workload – sessions used for short term troubleshooting will likely fall into the “reasonably expected impact” category. Hey buddy – I think you forgot something OK, there are two options I didn’t cover: STARTUP_STATE & TRACK_CAUSALITY. If you want your event sessions to start automatically when the server starts, set the STARTUP_STATE option to ON. (Now there is only one option I didn’t cover.) I’m going to leave causality for another post since it’s not really related to session behavior, it’s more about event analysis. - Mike Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • performing a javascript event without triggering that event handler

    - by bento
    In my latest code, I have an event handler for a focus on a textarea. When the user clicks on the textarea, that event-handler is triggered which sets some other DOM states based on the selected textarea. However, elsewhere in my program I want to programmatically set the focus of the textarea without triggering that event handler. I know Backbone, for instance, has a way to silently perform an action. My only pseudo-solution is to temporarily set a variable: var silence = true; And then, in my event handler, only perform the logic if silence is false. The handler is still triggered, but the logic doesn't run. Does anyone else know of better strategies for this?

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  • Event ID: 861 - The Windows Firewall has detected an application listening for incoming traffic

    - by Chris Marisic
    Firstly, my machines aren't compromised any person suggesting such will be DV'd. The security logs on some of my networks client machines (all Windows Xp Sp3) get filled with these useless error messages. Security Failure Audit Detailed Tracking Event ID: 861 User: NT AUTHORITY\NETWORK SERVICE The Windows Firewall has detected an application listening for incoming traffic. Name: - Path: C:\WINDOWS\system32\svchost.exe Process identifier: 976 User account: NETWORK SERVICE User domain: NT AUTHORITY Service: Yes RPC server: No IP version: IPv4 IP protocol: UDP Port number: 55035 Allowed: No User notified: No It's always on various random ports of UDP so setting up a port exception isn't really an option. It's always from svchost or lsass both of which are running services from DLLs. One of the most offending processes seems to the be DnsCache. I have in my global policy under AT < Network < Network Connection < Widnows Firewall < Domain Profile (I haven't changed any standard profile options do both need configured? To allow remote administration and desktop exceptions and have a custom program exception list that has %SystemRoot%\system32\svchost.exe:*:enabled:svchost (Windows won't allow you to add this exception on a local machine but it let me have it on here in the global policy it just doesn't seem to do anything) %SystemRoot%\system32\lsass.exe:*enabled:lsass (I think this one ended all of my LSASS messages) %SystemRoot%\system32\dnsrslvr.dll:*:enabled:dnscache (I tried adding the dll itself to the exception list, this didn't seem to do anything) Is there really any other options left other than disabling the Windows Firewall entirely, disabling auditing entirely or just changing the event viewer to just auto overwrite when needed? I'd much rather fix the problem and get rid of these entries ever being created instead of just trying to cover up the problem.

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  • DDD North 3 Presentation and source code &ndash; &lsquo;Event Store - an introduction to a DSD for event sourcing and notifications&rsquo;

    - by Liam Westley
    Originally posted on: http://geekswithblogs.net/twickers/archive/2013/10/15/ddd-north-3-presentation-and-source-code-ndash-lsquoevent-store.aspxThank you everyone at DDD North Thanks to all the people who helped organise the cracking conference that is DDD North 3, returning to Sunderland, and the great facilities at the University of Sunderland, and the fine drinks reception at Sunderland Software City.  The whole event wouldn’t be possible without the sponsors who ensured over 400 people were kept fed and watered so they could enjoy the impressive range of sessions. And lastly, a thank you to all those delegates who gave up their free time on a Saturday to spend a day dashing between lecture rooms, including a late change to my room which saw 40 people having to brave a journey between buildings in the fine drizzle. The enthusiasm from the delegates always helps recharge my geek batteries. Presentation and source code My presentation, source code, Event Store runners and text files containing the various command line parameters used for curl is now available on GitHub; https://github.com/westleyl/DDDNorth3-EventStore. Don’t worry if you don’t have a GitHub account, you don’t need one, you can just click on the Download Zip button on the right hand menu to download all the files as a single ZIP file.  If all you want is the PowerPoint presentation, go to https://github.com/westleyl/DDDNorth3-EventStore/blob/master/Powerpoint/DDDNorth-EventStore.pptx, and click on the View Raw button. Downloading and installing Event Store and Tools Download Event Store http://download.geteventstore.com – I unzipped these files into C:\EventStore\v2.0.1 Download Curl from http://curl.haxx.se/download.html – I downloaded Win64 Generic (with SSL) and unzipped these files into C:\curl version 7.31.0 Running the tools I used in my presentation Demonstration 1 (running Event Store) You can use one of my Event Store runner command files to run the single node version of Event Store, using default ports of 2213 for HTTP and 1113  for TCP, and with a wildcard HTTP pattern.  Both take a single command line parameter to specify the location of the data and log files.  The runners assume the single node executable is located in C:\EventStore\v2.0.1, and will placed data files and logs beneath C:\EventStore\Data, i.e. RunEventStore.cmd TestData1 This will create data files in C:\EventStore\Data\TestData1\Data and log files in C:\EventStore\Data\TestData1\logs. If, when running Event Store you may see the following message, [03288,15,06:23:00.622] Failed to start http server Access is denied You will either need to run Event Store in an administrator console window, or you can use the netsh command to create a firewall permission to allow HTTP listening (this will need to be run, once, in an administrator console window), netsh http add urlacl url=http://*:2213/ user=liam You can always delete this later by running the delete; netsh http delete urlacl url=http://*:2213/ If you want to confirm that everything is running OK, open the management console in a browser by navigating to http://127.0.0.1:2213. If at any point you are asked for a user name and password use the default of ‘admin’/‘changeit’.   Demonstration 2 (reading and adding data, curl) In my second demonstration I used curl directly from the console to read streams, write events and then read back those events. On GitHub I have included is a set of curl commands, CurlCommandLine.txt, and a sample data file, SampleData.json, to load an event into a DDDNorth3 stream. As there is not much data in the Event Store at this point I used the $stats-127.0.0.1:2113 which is a stream containing performance statistics for Event Store and is updated every 30 seconds (default). Demonstration 3 (projections) On GitHub I have included a sample projection, Projection-ByRoom.txt, which will create streams based on the room on which a session was held on the DDDNorth3 agenda. Browse to the management console, http://127.0.0.1:2213.  Click on Projections, New Projection, give it a name, Sessions-ByRoom, and copy in the JavaScript in the Projection-ByRoom.txt file.  Select Continuous, tick Emit Enabled and then click on Post. It should run immediately. You may by challenged for the administration login for the management console, if so use the default user name and password; 'admin'/'changeit'.   Demonstration 4 (C# client) The final demonstration was the Visual Studio 2012 project using the Event Store client – referenced directly as C:\EventStore\v2.0.1\EventStore.ClientAPI.dll, although you can switch this to the latest Event Store client NuGet package. The source code provides a console app for viewing projections with the projection manager (HTTP connection), as well as containing a full set of data for the entire DDDNorth3 agenda.  It also deals with the strategy for reading newest events backwards to older events and ignoring older events that have been superseded. Resources Event Store home page: http://www.geteventstore.com/ Event Store source code on GitHub: https://github.com/eventstore/eventstore Event Store documentation on GitHub: https://github.com/eventstore/eventstore/wiki (includes index to @RobAshton’s blog series on Event Store at https://github.com/eventstore/eventstore/wiki#rob-ashton---projections-series) Event Store forum in Google Groups: https://groups.google.com/forum/?fromgroups#!forum/event-store TopShelf Windows service wrapper is available on github: https://gist.github.com/trbngr/5083266

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  • Event ID for modified GPOs

    - by Hinek
    I have to know, who (usersid or loginname) changed a specified GPO for a specified OU in the Active Directory. Given our audit settings include this, what would be the right Event ID to look for?

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  • C# - Removing event handlers - FormClosing event or Dispose() method

    - by Andy
    Suppose I have a form opened via the .ShowDialog() method. At some point I attach some event handlers to some controls on the form. e.g. // Attach radio button event handlers. this.rbLevel1.Click += new EventHandler(this.RadioButton_CheckedChanged); this.rbLevel2.Click += new EventHandler(this.RadioButton_CheckedChanged); this.rbLevel3.Click += new EventHandler(this.RadioButton_CheckedChanged); When the form closes, I need to remove these handlers, right? At present, I am doing this when the FormClosing event is fired. e.g. private void Foo_FormClosing(object sender, FormClosingEventArgs e) { // Detach radio button event handlers. this.rbLevel1.Click -= new EventHandler(this.RadioButton_CheckedChanged); this.rbLevel2.Click -= new EventHandler(this.RadioButton_CheckedChanged); this.rbLevel3.Click -= new EventHandler(this.RadioButton_CheckedChanged); } However, I have seen some examples where handlers are removed in the Dispose() method. Is there a 'best-practice' way of doing this? (Using C#, Winforms, .NET 2.0) Thanks.

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