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  • ssrs 2008 programmatically add tables rows

    - by davethecoder
    Above is how my report looks, the part in yellow in hidden, and is only shown when the user clicks the + icon on the [name]. the result is basically the percentage difference from the Past [X] - [TERM] i.e there is a dropdown with, [weeks, months, days, hours] and a textbox of qty. so choosing qty = 4 and term = weeks will delivery a result set spread over 4 weeks based on the parent result sets date range and name ID I wish to populate here the number of rows, dependant on the value set by the user and the data will be from a dataset. Is it possible to dynamically add more sub rows ( like on row data bound ) if my first row is ID 123 [name], is it possible to send this value [123] to a dataset in order that all subrows are only relevant to the name with ID of 123? this is my first bash at SSRS so please no half cut answers, that just lead to more questions about the answer given :-) if this makes sense. Thanks

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  • How to easily Generate Synth Chords Sounds in Android?

    - by barata7
    How to easily Generate Synth Chords Sounds in Android? I wanna be able to generate dynamically an in game Music using 8bit. Tried with AudioTrack, but did not get good results of nice sounds yet. Any examples out there? I have tried the following code without success: public class BitLoose { private final int duration = 1; // seconds private final int sampleRate = 4200; private final int numSamples = duration * sampleRate; private final double sample[] = new double[numSamples]; final AudioTrack audioTrack; public BitLoose() { audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, sampleRate, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_8BIT, numSamples, AudioTrack.MODE_STREAM); audioTrack.play(); } public void addTone(final int freqOfTone) { // fill out the array for (int i = 0; i < numSamples; ++i) { sample[i] = Math.sin(2 * Math.PI * i / (sampleRate / freqOfTone)); } // convert to 16 bit pcm sound array // assumes the sample buffer is normalised. final byte generatedSnd[] = new byte[numSamples]; int idx = 0; for (final double dVal : sample) { // scale to maximum amplitude final short val = (short) ((((dVal * 255))) % 255); // in 16 bit wav PCM, first byte is the low order byte generatedSnd[idx++] = (byte) (val); } audioTrack.write(generatedSnd, 0, sampleRate); } public void stop() { audioTrack.stop(); }

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  • Split UInt32 (audio frame) into two SInt16s (left and right)?

    - by morgancodes
    Total noob to anything lower-level than Java, diving into iPhone audio, and realing from all of the casting/pointers/raw memory access. I'm working with some example code wich reads a WAV file from disc and returns stereo samples as single UInt32 values. If I understand correctly, this is just a convenient way to return the 32 bits of memory required to create two 16 bit samples. Eventually this data gets written to a buffer, and an audio unit picks it up down the road. Even though the data is written in UInt32-sized chunks, it eventually is interpreted as pairs of 16-bit samples. What I need help with is splitting these UInt32 frames into left and right samples. I'm assuming I'll want to convert each UInt32 into an SInt16, since an audio sample is a signed value. It seems to me that for efficiency's sake, I ought to be able to simply point to the same blocks in memory, and avoid any copying. So, in pseudo-code, it would be something like this: UInt32 myStereoFrame = getFramefromFilePlayer; SInt16* leftChannel = getFirst16Bits(myStereoFrame); SInt16* rightChannel = getSecond16Bits(myStereoFrame); Can anyone help me turn my pseudo into real code?

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  • Information about PTE's (Page Table Entries) in Windows

    - by Patrick
    In order to find more easily buffer overflows I am changing our custom memory allocator so that it allocates a full 4KB page instead of only the wanted number of bytes. Then I change the page protection and size so that if the caller writes before or after its allocated piece of memory, the application immediately crashes. Problem is that although I have enough memory, the application never starts up completely because it runs out of memory. This has two causes: since every allocation needs 4 KB, we probably reach the 2 GB limit very soon. This problem could be solved if I would make a 64-bit executable (didn't try it yet). even when I only need a few hundreds of megabytes, the allocations fail at a certain moment. The second problem is the biggest one, and I think it's related to the maximum number of PTE's (page table entries, which store information on how Virtual Memory is mapped to physical memory, and whether pages should be read-only or not) you can have in a process. My questions (or a cry-for-tips): Where can I find information about the maximum number of PTE's in a process? Is this different (higher) for 64-bit systems/applications or not? Can the number of PTE's be configured in the application or in Windows? Thanks, Patrick PS. note for those who will try to argument that you shouldn't write your own memory manager: My application is rather specific so I really want full control over memory management (can't give any more details) Last week we had a memory overwrite which we couldn't find using the standard C++ allocator and the debugging functionality of the C/C++ run time (it only said "block corrupt" minutes after the actual corruption") We also tried standard Windows utilities (like GFLAGS, ...) but they slowed down the application by a factor of 100, and couldn't find the exact position of the overwrite either We also tried the "Full Page Heap" functionality of Application Verifier, but then the application doesn't start up either (probably also running out of PTE's)

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  • Fastest way to find the rotation of a vector

    - by kriss
    I have two 2D vectors, say u and v, defined by cartesian coordinates. Imagine that vectors are needles of a clock. I'm looking for the fastest way to find out, using python, if v is after or before u (or in other words find out in wich half plane is v, regarding to position of u). For the purpose of the problem if vectors are aligned answer should be before. It seems easy using some trigonometry, but I believe there should be a faster way using coordinates only. My test case: def after(u, v): """code here""" after((4,2), (6, 1)) : True after((4,2), (3, 3)) : False after((4,2), (2, 1)) : False after((4,2), (3, -3)) : True after((4,2), (-2, -5)) : True after((4,2), (-4, -2)) : False

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  • Using sessions & session variables in a PHP Login Script

    - by user1325291
    I have just finished creating an entire login and register systsem in PHP, but my problem is I haven't used any sessions yet. (Like, there's not the word "session" in the entire script). I'm kind of a newbie in PHP and I've never used sessions before. What I want to do it, after the user registers and fills out the login form, they will still stay on the same page. So, like one half of the page will be if the session is logged_in and the other part will be else (the user is not logged in so display the login form). I also want to create session variables which will hold the username and password given at login. Thanks in advance! BTW this is my website - CP Cheats

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  • Android: Get the screen resolution / pixels as integer values

    - by poeschlorn
    Hi guys, this is a really simple question on which I've found no answer :/ How can I quickly access the screen resolution (width, height) as integer values? I've tried this one, but it always shows zero on my emulator: DisplayMetrics dm = new DisplayMetrics(); int width = dm.widthPixels / 2; In my case I want to dynamically create a table with tableRows, each containing two cols. This cols all shall fill half of the screen in width. Can someone give me a hint?

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  • ctypes DLL with optional dependencies

    - by pisswillis
    Disclaimer: I'm new to windows programming so some of my assumptions may be wrong. Please correct me if so. I am developing a python wrapper for a C API using ctypes. The API ships with both 64 and 32 DLLs/LIBs. I can succesfully load the DLL using ctypes.WinDLL('TheLibName') and call functions etc etc. However some functions were not doing what they should. Upon further investigation it appears that the 32bit DLL is being used, which is what is causing the unexpected behaviour. I have tried using ctypes.WinDLL('TheLibName64') but the module is not found. I have tried registering the DLL with regsrv32, but it reports there is no entry point (it also reports no entry point when I try and register TheLibName, which is found by WinDLL(). The DLL came with a sample project in Visual Studio (I have 0 experience with VS so again please correct me here) which builds both 32 and 64 bit versions of the sample project. In the .vcsproj file the configurations for the 64 bit version include: AdditionalDependencies="TheLibName64.lib" in the VCLinkerTool section. In windows/system32 there are both TheLibName.dll/.lib, and TheLibName64.dll/.lib. So it seems to me that my problem is now to make the python ctypes DLL loader load these optional dependencies when the DLL is loaded. However I can't find any information on this (perhaps because, as a doze noob, I do not know the correct terminology) in the ctypes documentation. Is there a way to do this in ctypes? Am I going about this in completely the wrong way? Any help or general information about optional DLL dependencies and how they are loaded in windows would be much appreciated. Thanks

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  • Why does placing this html within form tags change the layout?

    - by user352687
    I'm using this free Web Template - EliteCircle and have just incorporated it into a master page. The master page wraps the html in: <form id="form1" runat="server"> //master page html </form> The template almost comes out fine except the entire page is surrounded by a think white border (default CSS behavior for form?) and the footer background is half white on the very bottom. I wouldn't expect the form with id=form1 to change anything in the layout. There is nothing in the [CSS][2] with that id. When I remove the form tags from the master page (just to check) the layout is perfect, no problems. Any ideas? (Using Visual Web Developer 2008 Express) Thanks, Greg The CSS: http://www.styleshout.com/templates/preview/EliteCircle12/images/EliteCircle.css

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  • EnumJobs not returning Copies & Total Pages

    - by Hein du Plessis
    I'm using Windows API's EnumJobs to find the PageCount and Copies of a print job, but I found that these fields are almost always zero when called on a print server. Although it could be my timing is out, because the number of pages increment as the job prints and once it's done the print job cannot be accessed. So there is about half a nanosecond when the values in EnumJobs is correct before it dissapears. I've been scouring the web but can't find any help on this, just other people with similar problems. Anybody with experience with EnumJobs or can suggest other means of determining the total number of pages printed?

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  • CRM 2011 - Set/Retrieve work hours programmatically

    - by Philip Rich
    I am attempting to retrieve a resources work hours to perform some logic I require. I understand that the CRM scheduling engine is a little clunky around such things, but I assumed that I would be able to find out how the working hours were stored in the DB eventually... So a resource has associated calendars and those calendars have associated calendar rules and inner calendars etc. It is possible to look at the start/end and frequency of aforementioned calendar rules and query their codes to work out whether a resource is 'working' during a given period. However, I have not been able to find the actual working hours, the 9-5 shall we say in any field in the DB. I even tried some SQL profiling while I was creating a new schedule for a resource via the UI, but the results don't show any work hours passing to SQL. For those with the patience the intercepted SQL statement is below:- EXEC Sp_executesql N'update [CalendarRuleBase] set [ModifiedBy]=@ModifiedBy0, [EffectiveIntervalEnd]=@EffectiveIntervalEnd0, [Description]=@Description0, [ModifiedOn]=@ModifiedOn0, [GroupDesignator]=@GroupDesignator0, [IsSelected]=@IsSelected0, [InnerCalendarId]=@InnerCalendarId0, [TimeZoneCode]=@TimeZoneCode0, [CalendarId]=@CalendarId0, [IsVaried]=@IsVaried0, [Rank]=@Rank0, [ModifiedOnBehalfBy]=NULL, [Duration]=@Duration0, [StartTime]=@StartTime0, [Pattern]=@Pattern0 where ([CalendarRuleId] = @CalendarRuleId0)', N'@ModifiedBy0 uniqueidentifier,@EffectiveIntervalEnd0 datetime,@Description0 ntext,@ModifiedOn0 datetime,@GroupDesignator0 ntext,@IsSelected0 bit,@InnerCalendarId0 uniqueidentifier,@TimeZoneCode0 int,@CalendarId0 uniqueidentifier,@IsVaried0 bit,@Rank0 int,@Duration0 int,@StartTime0 datetime,@Pattern0 ntext,@CalendarRuleId0 uniqueidentifier', @ModifiedBy0='EB04662A-5B38-E111-9889-00155D79A113', @EffectiveIntervalEnd0='2012-01-13 00:00:00', @Description0=N'Weekly Single Rule', @ModifiedOn0='2012-03-12 16:02:08', @GroupDesignator0=N'FC5769FC-4DE9-445d-8F4E-6E9869E60857', @IsSelected0=1, @InnerCalendarId0='3C806E79-7A49-4E8D-B97E-5ED26700EB14', @TimeZoneCode0=85, @CalendarId0='E48B1ABF-329F-425F-85DA-3FFCBB77F885', @IsVaried0=0, @Rank0=2, @Duration0=1440, @StartTime0='2000-01-01 00:00:00', @Pattern0=N'FREQ=WEEKLY;INTERVAL=1;BYDAY=SU,MO,TU,WE,TH,FR,SA', @CalendarRuleId0='0A00DFCF-7D0A-4EE3-91B3-DADFCC33781D' The key parts in the statement are the setting of the pattern:- @Pattern0=N'FREQ=WEEKLY;INTERVAL=1;BYDAY=SU,MO,TU,WE,TH,FR,SA' However, as mentioned, no indication of the work hours set. Am I thinking about this incorrectly or is CRM doing something interesting around these work hours? Any thoughts greatly appreciated, thanks.

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  • How can I view javadocs that have been added to a maven repository?

    - by Coderer
    I know I can use maven to pull the javadocs for an artifact (if they've been added), which should come through as a JAR (right?), which I can then unpack and browse. My problem is, I'm trying to figure out which of a series of artifacts have the particular package I'm hunting for. I could download a half-dozen javadoc packages, unpack all of them, then open the index files one at a time, but that sounds like it would be pretty unpleasant. There must be a better way! I noticed that Nexus supports javadoc artifact browsing, but apparently only in the Pro version (which we do not have, and are unlikely to get any time soon). I'd prefer a GUI solution, though I'd settle for a command line answer, provided it's something along the lines of showmethedocs groupId:artifactId [version].

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  • how to debug a query that has valid syntax, executes, but returns no results?

    - by Ty W
    So I'm writing a fairly involved query with a half dozen joins, a dependent subquery for [greatest-n-per-group] purposes, grouping, etc. It is syntactically valid, but I've clearly made at least one mistake because it returns nothing. In the past I've debugged valid queries that return nothing by removing joins, executing subqueries on their own, removing WHERE conditions, and removing grouping to see what I would get but so far this one has me stumped. Are there better tools or techniques to use for this sort of thing? This particular query is for MySQL if it matters for any platform-specific tools.

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  • Jquery tooltip plugin qTip doesn't seem to set width properly

    - by ooo
    i have an asp.net mvc site and here is a dynamic tooltip using qTip Here is my code: $('a.showNutritionInfo').each(function() { $(this).qtip({ content: { text: '<img src="../../images/ajax-loader1.gif" alt="" />', style: { width: 450 }, url: '/Tracker/NutritionInfo/' + $(this).attr('id'), method: 'get' } }); }); this works perfectly EXCEPT the width attribute listed above is ignored. No matter what i put in that width attribute, i get the same size width tooltip which is about half of the width that i need. the height is perfectly fine. any ideas? is this a bug in the product ?

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  • JQuery.ready is too late: How do I apply CSS Values with JQuery before Rendering?

    - by viatropos
    I want to be able to apply opacity to some elements to make them invisible only if javascript is enabled. I don't want to use display:none because I want the layout to act as if they're in the DOM, so setting opacity to 0 is perfect. I want to be able to set this initial value using Javascript, using JQuery, so I don't have to mess with browser differences on the opacity (and many other) attributes. But if I set opacity to 0 like so: $(document).ready(function() { $("#header").css("opacity", 0); $("#header").animate({opacity:1}, 500); }); ...half the time it's already visible on the screen, so it appears and disappears. How do I set these css values using JQuery before they ever can render?

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  • CakePHP: How can I disable auto-increment on Model.id?

    - by tomws
    CakePHP 1.3.0, mysqli I have a model, Manifest, whose ID should be the unique number from a printed form. However, with Manifest.id set as the primary key, CakePHP is helping me by setting up auto-increment on the field. Is there a way to flag the field via schema.php and/or elsewhere to disable auto-increment? I need just a plain, old primary key without it. The only other solution I can imagine is adding on a separate manifest number field and changing foreign keys in a half dozen other tables. A bit wasteful and not as intuitive.

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  • Find a specific couple of lines of code from large git repo

    - by mustISignUp
    So i remember that i once did something in another project and (later removed it), that could be useful now. Thanks to some other SO post i managed to search for a half remembered string.. git grep halfRemeberedNameOfFunction $(git log -g --pretty=format:%h) and Yay! got some results 2d0bcde:path/to/project/file.c: result = halfRemeberedNameOfFunction( data ); 65fc672:path/to/project/file.c: result = halfRemeberedNameOfFunction( data ); 24f2858:path/to/project/file.c: result = halfRemeberedNameOfFunction( data ); 252e3a5:path/to/project/file.c: result = halfRemeberedNameOfFunction( data, args ); b58bc0b:path/to/project/file.c: result = _halfRemeberedNameOfFunction( data, options ); dce8d9d:path/to/project/file.c: result = halfRemeberedNameOfFunction( data, moreData ); But how do i get that file at one of those revisions? Many thanks

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  • C# Drag and Drop Effect with Overlay/Opaque Image

    - by CallMeLaNN
    Hi, I think this would be simple question and should be asked in the pas few years but unable to google around and dont know if there is a specific keyword. In c# WinForm I want to do drag and drop but I dont want the image of DragDropEffects Move, Copy or whatever. I want to display an image with half opaque. Just like Firefox when dragging an image, you would see the image folowing the mouse pointer like a ghost :) I already Implement DoDragDrop, DragEnter and DragDrop events. I just want to customize the dragging effects with overlay image.

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  • Given a short (2-week) sprint, is it ever acceptable to forgo TDD to "get things done"?

    - by Ben Aston
    Given a short sprint, is it ever acceptable to forgo TDD to "get things done" within the sprint. For example a given piece of work might need say 1/3 of the sprint to design the object model around an existing implementation. Under this scenario you might well end up with implemented code, say half way through the sprint, without any tests (implementing unit tests during this "design" stage would add significant effort and the tests would likely be thrown away a few times until the final "design" is settled upon). You might then spend a day or two in the second week adding in unit / integration tests after the fact. Is this acceptable?

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  • What is the appropriate granularity in building a ViewModel?

    - by JasCav
    I am working on a new project, and, after seeing some of the difficulties of previous projects that didn't provide enough separation of view from their models (specifically using MVC - the models and views began to bleed into each other a bit), I wanted to use MVVM. I understand the basic concept, and I'm excited to start using it. However, one thing that escapes me a bit - what data should be contained in the ViewModel? For example, if I am creating a ViewModel that will encompass two pieces of data so they can be edited in a form, do I capture it like this: public PersonAddressViewModel { public Person Person { get; set; } public Address Address { get; set; } } or like this: public PersonAddressViewModel { public string FirstName { get; set; } public string LastName { get; set; } public string StreetName { get; set; } // ...etc } To me, the first feels more correct for what we're attempting to do. If we were doing more fine grain forms (maybe all we were capturing was FirstName, LastName, and StreetAddress) then it might make more sense to go down to that level. But, I feel like the first is correct since we're capturing ALL Person data in the form and ALL Address data. It seems like it doesn't make sense (and a lot of extra work) to split things apart like that. Appreciate any insight.

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  • Organising files and classes in XCode (iPhone application)

    - by pulegium
    It's a generic question and really a newbie one too, so bear with me... I'm playing with some iPhone development, and trying to create a simple "flip type" application. Nothing sophisticated, let's say on the flip side is a short application summary, bit like 'help' and on the main screen is a simple board game, let's say tic-tac-toe or similar. Now, XCode has generated me 'Main View', 'Flipside View' and 'Application Delegate' folders, with default template files in them. Now the question is where do I create appropriate 'MVC' classes? Let's say (V)iew classes are going to be the ones that have been automatically created. So the Flipside view class is responsible for generating text/images etc on the 'help' view. 'Main View' class is what draws the items on the table and updates the counters, etc. Where should I place the 'controller' class? And also, should it only be dealing with proxying only to the model? According to this the controller method is called from the view and manipulates the method classes. Similarly, the results from model are passed back to the view class by the controller issuing the calls to appropriate view methods. Similarly, where does the model class go? or should I just create a new folder for each, controller and model class files? What I'm after is the best practices, or just a short description how people normally structure their applications. I know it's very specific and also undefined... I came from Django background, so the way stuff is organised there is slightly different. Hope this makes sense, sorry if it's all bit vague, but I have to start somewhere :) And yes I've read quite few docs on the apple developer site, but trouble is that the documents are either going into too much detail about the language/framework/etc and the examples are way too simplistic. Actually, this leads me to the final question, has anyone know any good example of relatively complete application tutorial which I could use as a reference in organising my files?...

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  • Design advices for quick navigation between view

    - by Thomas Joulin
    Usually, when a View requires a lot of bindings, or some UI Elements like a Bing Map, it takes a "while" to load (like between half a second and a second). I don't want a delay between a "tap" action (like tapping an element on a ListBox) and the navigation action (displaying a new page). I don't mind displaying the page progressively. For example, for a Bing Map, I don't mind displaying a black page with only a title, and a second later, having the Map appear. What are the best practices ? It could post a sample if i'm not clear enough

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  • Combining two queries on same table

    - by user1830856
    I've looked through several previous questions but I am struggling to apply the solutions to my specific example. I am having trouble combining query 1 and query 2. My query originally returned (amongst other details) the values "SpentTotal" and "UnderSpent" for all members/users for the current month. My issue has been adding two additional columns to this original quert that will return JUST these two columns (Spent and Overspent) but for the previous months data Original Query #1: set @BPlanKey = '##CURRENTMONTH##' EXECUTE @RC = Minimum_UpdateForPeriod @BPlanKey SELECT cm.clubaccountnumber, bp.Description , msh.PeriodMinObligation, msh.SpentTotal, msh.UnderSpent, msh.OverSpent, msh.BilledDate, msh.PeriodStartDate, msh.PeriodEndDate, msh.OverSpent FROM MinimumSpendHistory msh INNER JOIN BillPlanMinimums bpm ON msh.BillingPeriodKey = @BPlanKey and bpm.BillPlanMinimumKey = msh.BillPlanMinimumKey INNER JOIN BillPlans bp ON bp.BillPlanKey = bpm.BillPlanKey INNER JOIN ClubMembers cm ON cm.parentmemberkey is null and cm.ClubMemberKey = msh.ClubMemberKey order by cm.clubaccountnumber asc, msh.BilledDate asc Query #2, query of all columns for PREVIOUS month, but I only need two (spent and over spent), added to the query from above, joined on the customer number: set @BPlanKeyLastMo = '##PREVMONTH##' EXECUTE @RCLastMo = Minimum_UpdateForPeriod @BPlanKeyLastMo SELECT cm.clubaccountnumber, bp.Description , msh.PeriodMinObligation, msh.SpentTotal, msh.UnderSpent, msh.OverSpent, msh.BilledDate, msh.PeriodStartDate, msh.PeriodEndDate, msh.OverSpent FROM MinimumSpendHistory msh INNER JOIN BillPlanMinimums bpm ON msh.BillingPeriodKey = @BPlanKeyLastMo and bpm.BillPlanMinimumKey = msh.BillPlanMinimumKey INNER JOIN BillPlans bp ON bp.BillPlanKey = bpm.BillPlanKey INNER JOIN ClubMembers cm ON cm.parentmemberkey is null and cm.ClubMemberKey = msh.ClubMemberKey order by cm.clubaccountnumber asc, msh.BilledDate asc Big thank you to any and all that are willing to lend their help and time. Cheers! AJ CREATE TABLE MinimumSpendHistory( [MinimumSpendHistoryKey] [uniqueidentifier] NOT NULL, [BillPlanMinimumKey] [uniqueidentifier] NOT NULL, [ClubMemberKey] [uniqueidentifier] NOT NULL, [BillingPeriodKey] [uniqueidentifier] NOT NULL, [PeriodStartDate] [datetime] NOT NULL, [PeriodEndDate] [datetime] NOT NULL, [PeriodMinObligation] [money] NOT NULL, [SpentTotal] [money] NOT NULL, [CurrentSpent] [money] NOT NULL, [OverSpent] [money] NULL, [UnderSpent] [money] NULL, [BilledAmount] [money] NOT NULL, [BilledDate] [datetime] NOT NULL, [PriorPeriodMinimum] [money] NULL, [IsCommitted] [bit] NOT NULL, [IsCalculated] [bit] NOT NULL, [BillPeriodMinimumKey] [uniqueidentifier] NOT NULL, [CarryForwardCounter] [smallint] NULL, [YTDSpent] [money] NOT NULL, [PeriodToAccumulateCounter] [int] NULL, [StartDate] [datetime] NOT NULL,

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  • How to limit TCP writes to particular size and then block untlil the data is read

    - by ustulation
    {Qt 4.7.0 , VS 2010} I have a Server written in Qt and a 3rd party client executable. Qt based server uses QTcpServer and QTcpSocket facilities (non-blocking). Going through the articles on TCP I understand the following: the original implementation of TCP mentioned the negotiable window size to be a 16-bit value, thus maximum being 65535 bytes. But implementations often used the RFC window-scale-extension that allows the sliding window size to be scalable by bit-shifting to yield a maximum of 1 gigabyte. This is implementation defined. This could have resulted in majorly different window sizes on receiver and sender end as the server uses Qt facilities without hardcoding any window size limit. Client 1st asks for all information it can based on the previous messages from the server before handling the new (accumulating) incoming messages. So at some point Server receives a lot of messages each asking for data of several MB's. This the server processes and puts it into the sender buffer. Client however is unable to handle the messages at the same pace and it seems that client’s receiver buffer is far smaller (65535 bytes maybe) than sender’s transmit window size. The messages thus get accumulated at sender’s end until the sender’s buffer is full too after which the TCP writes on sender would block. This however does not happen as sender buffer is much larger. Hence this manifests as increase in memory consumption on the sender’s end. To prevent this from happening, I used Qt’s socket’s waitForBytesWritten() with timeout set to -1 for infinite waiting period. This as I see from the behaviour blocks the thread writing TCP data until the data has actually been sensed by the receiver’s window (which will happen when earlier messages have been processed by the client at application level). This has caused memory consumption at Server end to be almost negligible. is there a better alternative to this (in Qt) if i want to restrict the memory consumption at server end to say x MB's? Also please point out if any of my understandings is incorrect.

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  • Rails test across multiple environments

    - by DSimon
    Is there some way to change Rails environments mid-way through a test? Or, alternately, what would be the right way to set up a test suite that can start up Rails in one environment, run the first half of my test in it, then restart Rails in another environment to finish the test? The two environments have separate databases. Some necessary context: I'm writing a Rails plugin that allows multiple installations of a Rails app to communicate with each other with user assistance, so that a user without Internet access can still use the app. They'll run a local version of an app, and upload their work to the online app by saving a file to a thumbdrive and taking it to an Internet cafe. The plugin adds two special environments to Rails: "offline-production" and "offline-test". I want to write functional tests that involve both the "test" and "offline-test" environments, to represent the main online version of the app and the local offline version of the app respectively.

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