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  • How do I use InputType=numberDecimal with the "phone" soft keypad?

    - by Adam Dunn
    For an EditText box, the user should only be entering valid numbers, so I am using android:inputType="numberDecimal". Unfortunately, the soft keyboard that Android brings up has numbers only along the top row, while the next three rows have various other symbols (dollar sign, percent sign, exclamation mark, space, etc). Since the numberDecimal only accepts numbers 0-9, negative sign, and decimal point, it would make more sense to use the "phone" soft keyboard (0-9 in a 3x3 grid, plus some other symbols). This would make the buttons larger and easier to hit (since it's a 4x4 grid rather than a 10x4 grid in the same screen area). Unfortunately, using android:inputType="phone" allows non-numeric characters such as parentheses I have attempted to use android:inputType="numberDecimal|phone", but the numberDecimal aspect of the bit flag seems to be ignored. I have also tried using android:inputType="phone" in combination with android:digits="0123456789-.", but that still allows multiple negative signs or decimal points (inputType="number" has really good error checking for things like that, and won't let the user even type it in). I have also tried using android:inputType="phone" in the xml layout file, while using a DigitsKeyListener in the java code, but then that just uses the default number soft keyboard (the one that has numbers only along top row) (it appears to set InputType.TYPE_CLASS_NUMBER, which voids the InputType.TYPE_CLASS_PHONE set by the xml layout). Writing a custom IME wouldn't work, since the user would have to select the IME as a global option outside the app. Is there any way to use the "phone" style soft keyboard while also using the "number" restrictions on what is entered?

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  • How accurately (in terms of time) does Windows play audio?

    - by MusiGenesis
    Let's say I play a stereo WAV file with 317,520,000 samples, which is theoretically 1 hour long. Assuming no interruptions of the playback, will the file finish playing in exactly one hour, or is there some occasional tiny variation in the playback speed such that it would be slightly more or slightly less (by some number of milliseconds) than one hour? I am trying to synchronize animation with audio, and I am using a System.Diagnostics.Stopwatch to keep the frames matching the audio. But if the playback speed of WAV audio in Windows can vary slightly over time, then the audio will drift out of sync with the Stopwatch-driven animation. Which leads to a second question: it appears that a Stopwatch - while highly granular and accurate for short durations - runs slightly fast. On my laptop, a Stopwatch run for exactly 24 hours (as measured by the computer's system time and a real stopwatch) shows an elapsed time of 24 hours plus about 5 seconds (not milliseconds). Is this a known problem with Stopwatch? (A related question would be "am I crazy?", but you can try it for yourself.) Given its usage as a diagnostics tool, I can see where a discrepancy like this would only show up when measuring long durations, for which most people would use something other than a Stopwatch. If I'm really lucky, then both Stopwatch and audio playback are driven by the same underlying mechanism, and thus will stay in sync with each other for days on end. Any chance this is true?

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  • JavaScript onchange, onblur, and focus weirdness in Firefox

    - by typoknig
    On my form I have a discount field that accepts a dollar amount to be taken off of the total bill (HTML generated in PHP): echo "<input id=\"discount\" class=\"text\" type=\"text\" name=\"discount\" onkeypress=\"return currency(this, event)\" onchange=\"currency_format(this)\" onfocus=\"on_focus(this)\" onblur=\"on_blur(this); calculate_bill()\"/><br/><br/>\n"; The JavaScript function calculate_bill calculates the bill and takes off the discount amount as long as the discount amount is less than the total bill: if(discount != ''){ if(discount - 0.01 > total_bill){ window.alert('Discount Cannot Be Greater Than Total Bill'); document.form.discount.focus(); } else{ total_bill -= discount; } } The problem is that even that when the discount is more than the total bill focus is not being returned to the discount field. I have tried calling the calculate_bill function with onchange but neither IE or Firefox will return focus to the discount field when I do it like that. When I call calculate_bill with onblur it works in IE, but still does not work in Firefox. I have attempted to use a confirmation box instead of an alert box as well, but that didn't work either (plus I don't want two buttons, I only an "OK" button). How can I ensure focus is returned to the discount field after a user has left that field by clicking on another field or tabbing IF the discount amount is larger than the total bill?

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  • C lang. -- Error: Segmentation fault

    - by user233542
    I don't understand why this would give me a seg fault. Any ideas? This is the function that returns the signal to stop the program (plus the other function that is called within this): double bisect(double A0,double A1,double Sol[N],double tol,double c) { double Amid,shot; while (A1-A0 > tol) { Amid = 0.5*(A0+A1); shot = shoot(Sol, Amid, c); if (shot==2.*Pi) { return Amid; } if (shot > 2.*Pi){ A1 = Amid; } else if (shot < 2.*Pi){ A0 = Amid; } } return 0.5*(A1+A0); } double shoot(double Sol[N],double A,double c) { int i,j; /*Initial Conditions*/ for (i=0;i<buff;i++) { Sol[i] = 0.; } for (i=buff+l;i<N;i++) { Sol[i] = 2.*Pi; } Sol[buff]= 0; Sol[buff+1]= A*exp(sqrt(1+3*c)*dx); for (i=buff+2;i<buff+l;i++) { Sol[i] = (dx*dx)*( sin(Sol[i-1]) + c*sin(3.*(Sol[i-1])) ) - Sol[i-2] + 2.*Sol[i-1]; } return Sol[i-1]; } The values buff, l, N are defined using a #define statement. l = 401, buff = 50, N = 2000

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  • How To Go About Updating Old C Code

    - by Ben313
    Hello: I have been working on some 10 year old C code at my job this week, and after implementing a few changes, I went to the boss and asked if he needed anything else done. Thats when he dropped the bomb. My next task was to go through the 7000 or so lines and understand more of the code, AND, to modularize the code somewhat. I asked him how he would like the source code modularized, and he said to start putting the old C code into c++ classes. Being a good worker, I nodded my head yes, and went back to my desk, where I sit now, wondering how in the world to take this code, and "modularize" it. Its already in 20 source files, each with its own purpose and function. in addition, there are three "main" structs. each of these stuctures has 30 plus fields, many of them being other, smaller sturcts. Its a complete mess to try to understand, but almost every single function in the program is passed a pointer to one of the structs, and uses the struct heavily. Is there any clean way for me to shoehorn this into classes? I am resolved to do it if it can be done, I just have no idea how to begin.

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  • JQuery UI drag and drop doesn't notice DOM changes happening during the dragging ?

    - by user315677
    Hi everybody, I have a html table in which each line (<tr>) represents a group of client computers. Each line can be expanded to show the clients belonging to the group. The <tr> containing the clients are always generated but hidden and showed when clicking the plus button at the beginning of each line. The clients themselves (they are <div>) can be dragged and dropped in another group as long as this group is already expanded. So far it works fine. What I am trying to achieve now is that the client can be dragged to a collapsed group and after a second or so hovering the group it will be expanded and the client can be dropped amongst the other clients of the group. I programmed the hover using the in and outevents of the droppable and it expands the group all right, but (and now it starts to be hard to explain with words ;) the behavior of the droppable (the client) is still as if the table line that appeared were not there : the in out and drop events of the droppable are fired on the old position of the elements, and the in out and drop events of the newly appeared <tr> are never fired. It looks as if JQuery memorizes the position, size etc. of the elements when the drag starts, and these values are not updated if there is a change in the DOM before the drop happens... Can someone confirm this behavior is normal, or can it be caused by another problem in my own code ? Any workaround ? (the question is quite bloated already so I don't include any code but I'll gladly upload it if required)

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  • Convert Excel Range to ADO.NET DataSet or DataTable, etc.

    - by htbrady
    I have an Excel spreadsheet that will sit out on a network share drive. It needs to be accessed by my Winforms C# 3.0 application (many users could be using the app and hitting this spreadsheet at the same time). There is a lot of data on one worksheet. This data is broken out into areas that I have named as ranges. I need to be able to access these ranges individually, return each range as a dataset, and then bind it to a grid. I have found examples that use OLE and have got these to work. However, I have seen some warnings about using this method, plus at work we have been using Microsoft.Office.Interop.Excel as the standard thus far. I don't really want to stray from this unless I have to. Our users will be using Office 2003 on up as far as I know. I can get the range I need with the following code: MyDataRange = (Microsoft.Office.Interop.Excel.Range) MyWorkSheet.get_Range("MyExcelRange", Type.Missing); The OLE way was nice as it would take my first row and turn those into columns. My ranges (12 total) are for the most part different from each other in number of columns. Didn't know if this info would affect any recommendations. Is there any way to use Interop and get the returned range back into a dataset?

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  • Servlet send image from server and save in client

    - by sangi
    Hi, I'm new and just developing on J2EE. I am modifying an existing application (an OpenSource project). I need to save an image on a client sent by the server, but I do not know how. This activity must be done in a transparent manner without affecting the existing operation of the application. From the tests done I get this error: java.lang.IllegalStateException: getWriter () has Already Been Called for this response. How should carry out this task, according to your own opinion? How do I save on the client, locally, the image? Update: Thanks for the answers. My problem is that: the image is generated on the server, but not for direct client request (there is no link to click on web page), the picture is composed using other services on the Internet. reconstruct the image on the server. This image must be sent to the client to be saved locally. so I'd like it to appear a window where you assign the destination image plus I'd like the rest of the application were not affected by this activity. The application is yet on production. Thank you very much for your response.

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  • Is there a simple way to "roll your own forms" for mysql in php, for example in jquery?

    - by talkingnews
    I've been googling around for a really simple way of making what is, in effect, nothing more than an enhanced phpMySql. In a mysql database, I have: Name, address, phone, website etc, plus 2 or 3 custom fields. This data is pulled out to make a website. All I want is to be able to make a freeform form, a bit like Access, but for the web, and the only thing I want to do over and above normal field editing would be to have a list of when I contact them, what was said, and perhaps a reminder when the next action is due. I've looked at so many CRMs my mind is boggling, and they all do WAY more than I need. I don't have leads or accounts, all I have is the need to make sure than when I update the person's details, and for that data to be in the same DB as my site is generate from. I'm happy to learn if I can get pointed in the right direction, and I have a feeling that something like what I want might lie in the direction of jquery. It's just that there's so much good jquery stuff about, I can't see the wood for the trees! Thanks.

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  • EF 4 Self Tracking Entities does not work as expected.

    - by ashraf
    I am using EF4 Self Tracking Entities (VS2010 Beta 2 CTP 2 plus new T4 generator). But when I try to update entity information it does not update to database as expected. I setup 2 service calls. one for GetResource(int id) which return a resource object. the second call is SaveResource(Resource res); here is the code. public Resource GetResource(int id) { using (var dc = new MyEntities()) { return dc.Resources.Where(d => d.ResourceId == id).SingleOrDefault(); } } public void SaveResource(Resource res) { using (var dc = new MyEntities()) { dc.Resources.ApplyChanges(res); dc.SaveChanges(); // Nothing save to database. } } //Windows Console Client Calls var res = service.GetResource(1); res.Description = "New Change"; // Not updating... service.SaveResource(res); // does not change anything. It seems to me that ChangeTracker.State is always show as "Unchanged". anything wrong in this code?

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  • architecture and tools for a remote control application?

    - by slothbear
    I'm working on the design of a remote control application. From my iPhone or a web browser, I'll send a few commands. Soon my home computer will perform the commands and send back results. I know there are remote desktop apps, but I want something programmable, something simpler, and something that I wrote. My current direction is to use Amazon Simple Queue Service (SQS) as the message bus. The iPhone places some messages in a queue. My local Java/JRuby program notices the messages on the queue, performs the work and sends back status via a different queue. This will be a very low-volume application. At $1.00 for a million requests (plus a handful of data transfer charges), Amazon SQS looks a lot more affordable than having my own server of any type. And super reliable, that's important for me too. Are there better/standard toolkits or architectures for this kind of remote control? Cost is not a big issue, but I prefer the tons I learn by doing it myself. I'm moderately concerned about security, but doubt it will be a problem. The list of commands recognized will be very short, and only recognized in specific contexts. No "erase hard drive" stuff. update: I'll probably distribute these programs to some other people who want the same function, but who don't have Amazon SQS accounts. For now, they'll use anonymous access to my queues, with random 80-character queue names.

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  • What is a good automated data import method for SQL Server?

    - by Joel Potter
    I'm in the process of porting some SQL Server 2005 databases to SQL Server 2008. One of these databases has an associated import application (Windows task) which uses SSIS with a DTS package to import a large dataset from an MS Access database nightly. In upgrading to SQL Server 2008, I discovered that I can't run the same console application which has been performing the imports due to the missing manageddts DLL in SQL Server 2008. It's several years old and in need of a rewrite for various reason, plus, I've been fairly unhappy with DTS in general. The original reason DTS was chosen was for speed (5 min import time compared to 30+ for ADO.NET). The format of the data to import is out of my control (the client likes Access). I would also like to be able to run the import from a machine completely separate from the server hosting SQL Server and preferably with minimal SQL features installed. Options I've considered: Creating an Access application to connect to both databases (SQL Server and Access) and perform the import (Ugh!) Revisiting ADO.NET to see if the original implementation was poorly written. Updated SSIS packages. What other technologies should I be considering for this job?

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  • What makes good web form styling for business applications?

    - by ProfK
    Styling forms (form elements) is something that even Eric Meyer prefers to avoid. However, most business forms, and that is where styling is at issue; 'contact us' forms are easy to style, put window estate at a premium, with more 'document level' (e.g. invoice) fields, plus 'detail level' (e.g. invoice line) fields. Factors I often find at play are: At my minimum, at least two horizontally adjacent fieldsets are required. In applications vs. public web pages, fixed positioning vs fluid layout is often better. Quantity of content is important, vs. exaggerated readability. Users know the system, and cues etc. take a back seat. In light of factors like these, is there any available guidence for styling web form based applications? Are there any CSS or JavaScript frameworks that would make my quest to style these applications better than Visual Studios still pathetic 'Auto-format' (what drugs were those people on? I will never take them.)

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  • How do I stop a routed event from triggering on specific places in XAML?

    - by cfouche
    I have the following situation: A stackpanel contains a number of elements, including some that are contained in a GroupBox. So something like this: <StackPanel x:Name="stackpanel" Background="White"> <TextBlock Text="TextBlock"/> <TextBlock Text="Another TextBlock"/> <!--plus a load of other elements and controls--> <GroupBox Header="GroupBoxHeader"> <TextBlock Text="Text inside GroupBox"/> </GroupBox> </StackPanel> I want a MouseDown in the stackpanel to trigger some Storyboard, so I've added an EventTrigger, like this: <EventTrigger RoutedEvent="Mouse.MouseDown" SourceName="stackpanel"> <BeginStoryboard Storyboard="{StaticResource OnMouseDown1}"/> </EventTrigger> This is almost right, but the thing is - I don't want the MouseDown to be picked up by the GroupBox's header or border, only by its content. In other words, I want the Storyboard to begin when someone does a mousedown on anything inside the StackPanel, except GroupBox headers and borders. Is there some way of doing this? (I've tried setting e.Handled to true on the GroupBox, but then its content doesn't pick up the mousedown anymore either.)

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  • how to rotate around each record in linq and show that in view

    - by Sadegh
    Hi, I have four tables in my database and i want to join that's and return record's and show that into searchController! My query is this: public IQueryable PerformSearch(string query) { if (!string.IsNullOrEmpty(query)) { var results = from tbl1 in context.Table1 join tbl2 in context.Table2 on tbl1.Id equals tbl2.Id join tbl3 in context.Table3 on tbl2.Id equals tbl3.Id join tbl4 in context.Table4 on tbl3.Id equals tbl4.Id where tbl1.col2.Contains(query) orderby tbl1.Count descending select new { col1 = tbl1.Col1, col1 = tbl1.Col1, col1 = tbl1.Col1, . . . }; return results.AsQueryable(); } else return null; } And this method called in SearchController as below: public class SearchController : System.Web.Mvc.Controller { public System.Web.Mvc.ActionResult Search(System.String query) { var search = new Search(); ViewData["result"] = search.PerformSearch(query); return View("Search"); } } I don't know how i can rotate around each record (plus vs intellisense feature) returned by PeformSeach method and show that in view! Also is this a good way? thanks in advance

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  • IIS URL Rewriting: How can I reliably keep relative paths when serving multiple files?

    - by NVRAM
    My WebApp is part CMS, and when I serve up an HTML page to the user it typically contains relative paths in a.href and img.src attributes. I currently have them accessed by urls like: ~/get-data.aspx/instance/user/page.html -- where instance indicates the particular instance for the report and "user/page.html" is a path created by an external application that generates the content. This works pretty reliably with code in the application's BeginRequest method that translates the text after ".aspx" into a query string, then uses Context.RewritePath(). So far so good, but I've just tripped over something that took me by surprise: it appears that if any of the query string ("instance/user/page.html") happens to contain a plus sign ("+") the BeginRequest method is never called, and a 404 is immediately returned to the user. So my question is two-fold: Am I correct in my belief that a "+" would cause the 404, and if so are there other things that could cause similar problems? Is there a way around that problem (perhaps a different method than BeginRequest)? Is there a better way to preserve relative URL paths for generated content than what I'm using? I'd rather not require site admins to install a 3rd party rewrite tool if I can help it.

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  • Update SQL Server 2000 to SQL Server 2008: Benefits please?

    - by Ciaran Archer
    Hi there I'm looking for the benefits of upgrading from SQL Server 2000 to 2008. I was wondering: What database features can we leverage with 2008 that we can't now? What new TSQL features can we look forward to using? What performance benefits can we expect to see? What else will make management go for it? And the converse: What problems can we expect to encounter? What other problems have people found when migrating? Why fix something that isn't (technically) broken? We work in a Java shop, so any .NET / CLR stuff won't rock our world. We also use Eclipse as our main development so any integration with Visual Studio won't be a plus. We do use SQL Server Management Studio however. Some background: Our main database machine is a 32bit Dell Intel Xeon MP CPU 2.0GHz, 40MB of RAM with Physical Address Extension running Windows Server 2003 Enterprise Edition. We will not be changing our hardware. Our databases in total are under a TB with some having more than 200 tables. But they are busy and during busy times we see 60-80% CPU utilisation. Apart form the fact that SQL Server 2000 is coming close to end of life, why should we upgrade? Any and all contributions are appreciated!

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  • How can I log any login operation in case of "Remember Me" option ?

    - by Space Cracker
    I have an asp.net login web form that have ( username textBox - password textBox ) plus Remember Me CheckBox option When user login i do the below code if (provider.ValidateUser(username, password)) { int timeOut = 0x13; DateTime expireDate = DateTime.Now.AddMinutes(19.0); if (rememberMeCheckBox.Checked) { timeOut = 0x80520; expireDate = DateTime.Now.AddYears(1); } FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(username, true, timeOut); string cookieValue = FormsAuthentication.Encrypt(ticket); HttpCookie cookie = new HttpCookie(FormsAuthentication.FormsCookieName, cookieValue); cookie.Expires = expireDate; HttpContext.Current.Response.Cookies.Add(cookie); AddForLogin(username); Response.Redirect("..."); } as in code after user is authenticated i log that he login in db by calling method AddForLogin(username); But if user choose remember me in login and then he try to go to site any time this login method isn't executed as it use cookies ... so i have many questions: 1- Is this the best way to log login operation or is there any other better ? 2- In my case how to log login operation in case of remember me chosen by user ?

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  • Is anyone familiar with SDPT.clsSDPT?

    - by David Stratton
    Normally I wouldn't ask this kind of question here, but I'm desperate at this point. I'm attempting to support a classic ASP app written by a predecessor who is no longer available. Keeping it short, several applications use a dll to perform encryption of sensitive data. This dll is named SDPT.dll, and the line of code used to create an object is set objSDPT = server.CreateObject("SDPT.clsSDPT") At this point, I am getting errors in a critical app on one of my servers, and I've actually hit a dead end. The error is a standard "Server.CreateObject Failed" message, which I know how to troubleshoot in most cases. However, in this case, all of my normal tries, plus several hours of Google searches are coming up with nothing that works. At this point, I'm not so much looking for help in troubleshooting the issue as I am in finding any sort of reference on this third party component. Even finding that is proving to be difficult, so I'm resorting to asking any of the seasoned developers that hang out here if they are familiar with this product, who it was developed by, and if any documentation on it exists anywhere.

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  • Django: Applying Calculations To A Query Set

    - by TheLizardKing
    I have a QuerySet that I wish to pass to a generic view for pagination: links = Link.objects.annotate(votes=Count('vote')).order_by('-created')[:300] This is my "hot" page which lists my 300 latest submissions (10 pages of 30 links each). I want to now sort this QuerySet by an algorithm that HackerNews uses: (p - 1) / (t + 2)^1.5 p = votes minus submitter's initial vote t = age of submission in hours Now because applying this algorithm over the entire database would be pretty costly I am content with just the last 300 submissions. My site is unlikely to be the next digg/reddit so while scalability is a plus it is required. My question is now how do I iterate over my QuerySet and sort it by the above algorithm? For more information, here are my applicable models: class Link(models.Model): category = models.ForeignKey(Category, blank=False, default=1) user = models.ForeignKey(User) created = models.DateTimeField(auto_now_add=True) modified = models.DateTimeField(auto_now=True) url = models.URLField(max_length=1024, unique=True, verify_exists=True) name = models.CharField(max_length=512) def __unicode__(self): return u'%s (%s)' % (self.name, self.url) class Vote(models.Model): link = models.ForeignKey(Link) user = models.ForeignKey(User) created = models.DateTimeField(auto_now_add=True) def __unicode__(self): return u'%s vote for %s' % (self.user, self.link) Notes: I don't have "downvotes" so just the presence of a Vote row is an indicator of a vote or a particular link by a particular user.

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  • What caused the rails application crash?

    - by so1o
    I'm sure someone can explain this. we have an application that has been in production for an year. recently we saw an increase in number of support requests for people having difficulty signing into the system. after scratching our head because we couldn't recreate the problem in development, we decided we'll switch on debug logger in production for a month. that was june 5th. application worked fine with the above change and we were waiting. then yesterday we noticed that the log files were getting huge so we made another change in production config.logger = Logger.new("#{RAILS_ROOT}/log/production.log", 50, 1048576) after this change, the application started crashing while processing a particular file. this particular line of code was RAILS_DEFAULT_LOGGER.info "Payment Information Request: ", request.inspect as you can see there was a comma instead of a plus sign. this piece of code was introduced in Mar. the question is this: why did the application fail now? if changing the debug level caused the application to process this line of code it should have started failing on june 5th! why today. please someone help us. Are we missing the obvious here? if you dont have an answer, at least let us know we aren't the only one that are bonkers.

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  • How to find an embedded platform?

    - by gmagana
    I am new to the locating hardware side of embedded programming and so after being completely overwhelmed with all the choices out there (pc104, custom boards, a zillion option for each board, volume discounts, devel kits, ahhh!!) I am asking here for some direction. Basically, I must find a new motherboard and (most likely) re-implement the program logic. Rewriting this in C/C++/Java/C#/Pascal/BASIC is not a problem for me. so my real problem is finding the hardware. This motherboard will have several other devices attached to it. Here is a summary of what I need to do: Required: 2 RS232 serial ports (one used all the time for primary UI, the second one not continuous) 1 modem (9600+ baud ok) [Modem will be in simultaneous use with only one of the serial port devices, so interrupt sharing with one serial port is OK, but not both] Minimum permanent/long term storage: Whatever O/S requires + 1 MB (executable) + 512 KB (Data files) RAM: Minimal, whatever the O/S requires plus maybe 1MB for executable. Nice to have: USB port(s) Ethernet network port Wireless network Implementation languages (any O/S I will adapt to): First choice Java/C# (Mono ok) Second choice is C/Pascal Third is BASIC Ok, given all this, I am having a lot of trouble finding hardware that will support this that is low in cost. Every manufacturer site I visit has a lot of options, and it's difficult to see if their offering will even satisfy my must-have requirements (for example they sometimes list 3 "serial ports", but it appears that only one of the three is RS232, for example, and don't mention what the other two are). The #1 constraint is cost, #2 is size. Can anyone help me with this? This little task has left me thinking I should have gone for EE and not CS :-). EDIT: A bit of background: This is a system currently in production, but the original programmer passed away, and the current hardware manufacturer cannot find hardware to run the (currently) DOS system, so I need to reimplement this in a modern platform. I can only change the programming and the motherboard hardware.

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  • How is a referencing environment generally implemented for closures?

    - by Alexandr Kurilin
    Let's say I have a statically/lexically scoped language with deep binding and I create a closure. The closure will consist of the statements I want executed plus the so called referencing environment, or, to quote this post, the collection of variables which can be used. What does this referencing environment actually look like implementation-wise? I was recently reading about ObjectiveC's implementation of blocks, and the author suggests that behind the scenes you get a copy of all of the variables on the stack and also of all the references to heap objects. The explanation claims that you get a "snapshot" of the referencing environment at the point in time of the closure's creation. Is that more or less what happens, or did I misread that? Is anything done to "freeze" a separate copy of the heap objects, or is it safe to assume that if they get modified between closure creation and the closure executing, the closure will no longer be operating on the original version of the object? If indeed there's copying being made, are there memory usage considerations in situations where one might want to create plenty of closures and store them somewhere? I think that misunderstanding of some of these concepts might lead to tricky issues like the ones Eric Lippert mentions in this blog post. It's interesting because you'd think that it wouldn't make sense to keep a reference to a value type that might be gone by the time the closure is called, but I'm guessing that in C# the compiler will figure out that the variable is needed later and put it into the heap instead. It seems that in most memory-managed languages everything is a reference and thus ObjectiveC is a somewhat unique situation with having to deal with copying what's on the stack.

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  • Career day in kindergarten

    - by Péter Török
    I was invited to the kindergarten group of my elder daughter to talk and answer the kids' questions about my profession. There are 26 kids of age 4-6 in the group, plus 3 teachers who are fairly scared of anything related to programming and IT themselves, but bold enough to learn new tricks. I would have about 20-30 minutes, without projector or anything. They have an old computer though, which by its look may be a 486, and I am not even sure if it's functioning. My research turned up excellent earlier threads, with lots of good tips: How would you explain your job to a 5-year old? Career Day: how do I make “computer programmer” sound cool to 8 year olds? What things can I teach a group of children about programming in one day? My situation is different from each of the above though: the latter ones are concerned with older children, while the first one is about talking to a single kid (or elder person)—a group of 20 is a whole different challenge. How can I teach the kids and their teachers about programming in a fun way?

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  • XSL - How to match consecutive comma-separated tags

    - by PocketLogic
    I'm trying to match a series of xml tags that are comma separated, and to then apply an xslt transformation on the whole group of nodes plus text. For example, given the following partial XML: <p>Some text here <xref id="1">1</xref>, <xref id="2">2</xref>, <xref id="3">3</xref>. </p> I would like to end up with: <p>Some text here <sup>1,2,3</sup>.</p> A much messier alternate would also be acceptable at this point: <p>Some text here <sup>1</sup><sup>,</sup><sup>2</sup><sup>,</sup><sup>3</sup>.</p> I have the transformation to go from a single xref to a sup: <xsl:template match="xref""> <sup><xsl:apply-templates/></sup> </xsl:template> But I'm at a loss as to how to match a group of nodes separated by commas. Thanks.

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