Search Results

Search found 54098 results on 2164 pages for 'something broken'.

Page 449/2164 | < Previous Page | 445 446 447 448 449 450 451 452 453 454 455 456  | Next Page >

  • Better language or checking tool?

    - by rwallace
    This is primarily aimed at programmers who use unmanaged languages like C and C++ in preference to managed languages, forgoing some forms of error checking to obtain benefits like the ability to work in extremely resource constrained systems or the last increment of performance, though I would also be interested in answers from those who use managed languages. Which of the following would be of most value? A language that would optionally compile to CLR byte code or to machine code via C, and would provide things like optional array bounds checking, more support for memory management in environments where you can't use garbage collection, and faster compile times than typical C++ projects. (Think e.g. Ada or Eiffel with Python syntax.) A tool that would take existing C code and perform static analysis to look for things like potential null pointer dereferences and array overflows. (Think e.g. an open source equivalent to Coverity.) Something else I haven't thought of. Or put another way, when you're using C family languages, is the top of your wish list more expressiveness, better error checking or something else? The reason I'm asking is that I have a design and prototype parser for #1, and an outline design for #2, and I'm wondering which would be the better use of resources to work on after my current project is up and running; but I think the answers may be useful for other tools programmers also. (As usual with questions of this nature, if the answer you would give is already there, please upvote it.)

    Read the article

  • Need help with jQuery/AJAX call in Safari/Mac

    - by protohominid
    I've got something that works perfectly in FF and MSIE but it's not working properly in Safari. It's a form with selects that get updated via AJAX/jQuery from a MySQL DB. In Safari, when you select the first item, it correctly loads the options for the next select menu; however, when you choose one of those (which loads new options in a subsequent select menu), the whole form resets and is broken from that point on. Does anyone know of a Safari bug that would cause this? Here's the JS: $(document).ready(function(){ $("#searchForm select").change(updateSearchForm); }); function updateSearchForm() { $.ajax({ url: '/elements/search_form.php?ajax=true', data: $('#searchForm').serialize(), error:function(xhr,err){ alert("readyState: "+xhr.readyState+"\nstatus: "+xhr.status); alert("responseText: "+xhr.responseText); }, success: function(data) { $("#searchForm").html(data); $("#searchForm select").change(updateSearchForm); } }); } I can post the relevant PHP/HTML for the form, but it's lengthy. I'm relatively new to JS so I'm not sure where to start debugging this... TIA

    Read the article

  • jQuery: How to use modifier keys on form submit?

    - by Svish
    Say I have a form that looks like this: [ Animal name input field ] Add button If I type a name and hit enter, an animal with the given name is added to a table. Works fine. What I would like now is to call the current way of working "quick add" and add a new feature called "slow add", which I am not quite sure how to do. Basically what I want is that if for example the shift key is held down when enter or the button is clicked, I want the form submit method to do something slightly different. In my case I want it to open up a form where more details on the animal can be added before it is added to the table. Problem is I'm not quite sure how to do this. I have tried add a FireBug console.info(eventData) in my current submit function and I have found that the eventData contains an altKey, shiftKey and controlKey property, but they are always undefined even when I hold those keys down. So, does anyone know how I can do something special in my submit handler when certain modifier keys were pressed when the form was submitted?

    Read the article

  • CSS horizontal scrolling overflow with jQuery slider

    - by Jeffrey
    I'm trying to setup a full screen jquery slider. I've broken the project into two steps 1) css and 2) js. 1) CSS, below is a picture of what I'm shooting for (no fixed height) and below that is the code I have so far that doesn't work. <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <style type="text/css"> /* Positioning */ #container { width: 2500px; } .block { display: inline; } /* Styling */ .block img { padding: 5px; } </style> </head> <body> <div id="container"> <div class="block"><img src="http://i42.tinypic.com/1zp2poz.gif"></div> <div class="block"><img src="http://i42.tinypic.com/1zp2poz.gif"></div> <div class="block"><img src="http://i42.tinypic.com/1zp2poz.gif"></div> </div> </body> </html> 2) Javascript, using jquery I'd like the divs to slide left when clicked on them... like the jQuery Coda Slider if possible. Thanks, any help is appreciated.

    Read the article

  • How to set buffer size in client-server app using sockets?

    - by nelly
    First of all i am new to networking so i may say dumb thing in here. Considering a client-server application using sockets(.net with c# if that matters). The client sends some data, the server process it and sends back a string. The client sends some other data, the serve process it, queries the db and sends back several hundreds of items from the database The client sends some other type of data and the server notifies some other clients . My question is how to set the buffer size correctly for reading/writing operation. Should i do something like this: byte[] buff = new byte[client.ReceiveBufferSize] ? I am thinking of something like this: Client sends data to the server(and the server will follow the same pattern) byte[] bytesToSend=new byte[2048] //2048 to be standard for any command send by the client bytes 0..1 ->command type bytes 1..2047 ->command parameters byte[] bytesToReceive=new byte[8]/byte[64]/byte[8192] //switch(command type) But..what is happening when a client is notified by the server without sending data? What is the correct way to accomplish what i am trying to do? Thanks for reading.

    Read the article

  • Best (Java) book for understanding 'under the bonnet' for programming?

    - by Ben
    What would you say is the best book to buy to understand exactly how programming works under the hood in order to increase performance? I've coded in assembly at university, I studied computer architecture and I obviously did high level programming, but what I really dont understand is things like: -what is happening when I perform a cast -whats the difference in performance if I declare something global as opposed to local? -How does the memory layout for an ArrayList compare with a Vector or LinkedList? -Whats the overhead with pointers? -Are locks more efficient than using synchronized? -Would creating my own array using int[] be faster than using ArrayList -Advantages/disadvantages of declaring a variable volatile I have got a copy of Java Performance Tuning but it doesnt go down very low and it contains rather obvious things like suggesting a hashmap instead of using an ArrayList as you can map the keys to memory addresses etc. I want something a bit more Computer Sciencey, linking the programming language to what happens with the assembler/hardware. The reason im asking is that I have an interview coming up for a job in High Frequency Trading and everything has to be as efficient as possible, yet I cant remember every single possible efficiency saving so i'd just like to learn the fundamentals. Thanks in advance

    Read the article

  • Why do I get null objects in a many-to-many bag?

    - by Jim Geurts
    I have a bag defined for a many-to-many list: <class name="Author" table="Authors"> <id name="Id" column="AuthorId"> <generator class="identity" /> </id> <property name="Name" /> <bag name="Books" table="Author_Book_Map" where="IsDeleted=0" fetch="join"> <key column="AuthorId" /> <many-to-many class="Book" column="BookId" where="IsDeleted=0" /> </bag> </class> If I return all author objects using something like the following, I will get what initially appeared to be duplicate Author records: Session.Query<Author>().List<Author>() The extra author objects are created when an author is mapped to Book objects that have IsDeleted = 1 and IsDeleted = 0. Rather than creating one Author object with an enumerable that contains only the books with IsDeleted = 0, it will create two author objects. The first author object has a Books enumerable that contains books with IsDeleted = 0. The second author object will contain an enumerable of null book objects. Similarly, if an object only has one book map, and that map points to a book with IsDeleted = 1, then an author object is returned with a Books collection having one null object. I'm thinking part of the problem stems from the map table objects linking to rows that satisfy the where condition on the bag object but do not meet the many-to-many where condition. This is happening with NHibernate version 3.0.0.4980. Is this a configuration issue or something else?

    Read the article

  • SQL Group by Minute- Expanded

    - by Barnie
    I am working on something similar to this post here: TS SQL - group by minute However mine is pulling from an message queue, and I need to see an accurate count of the amount of traffic the Message Queue is creating/ sending, and at what time Select * From MessageQueue mq My expanded version of this though is the following: A) User defines a start time and an end time (Easy enough using Declare's @StartTime and @EndTime B) Give the user the option of choosing the "grouping". Will it be broken out by 1 minutes, 5 minutes, 15 minutes, or 30 minutes (Max). (I had thought to do this with a CASE statement, but my test problems fall apart on me.) C) Display the data to accurately show a count of what happened during the interval (Grouping) selected. This is where I am at so far SQL Blob: DECLARE @StartTime datetime DECLARE @EndTime datetime SELECT DATEPART(n, mq.cre_date)/5 as Time --Trying to just sort by 5 minute intervals ,CONVERT(VARCHAR(10),mq.Cre_Date,101) ,COUNT(*) as results FROM dbo.MessageQueue mq WHERE mq.cre_date BETWEEN @StartDate AND @EndDate GROUP BY DATEPART(n, mq.cre_date)/5 --Trying to just sort by 5 minute intervals , eq.Cre_Date This is the output I would like to achieve: [Time] [Date] [Message Count] 1300 06/26/2012 5 1305 06/26/2012 1 1310 06/26/2012 100

    Read the article

  • How can I include DBNull as a value in my strongly typed dataset?

    - by Beska
    I've created a strongly typed dataset (MyDataSet) in my .NET app. For the sake of simplicity, we'll say it has one DataTable (MyDataTable), with one column (MyCol). MyCol has its DataType property set to "System.Int32", and its AllowDBNull property set to "true". I'd like to manually create a new row, and add it to this dataset. I create the row without a problem, with something like: MyDataSet.MyDataTableRow myRow = MySimpleDataSet.MyDataTable.NewItemRow(); Fine. However, when I try to set the value to DBNull: myRow.MyCol = DBNull.Value; I'm told that I can't do it...that it can't cast that to an int. This makes sense, in a way, since I've defined it to be an int...but then how can I get DBNull in there? Am I not supposed to be able to have DBNull in there? Isn't that what the AllowDBNull property is for? I'm obviously missing something fundemental. Can someone help explain what it is? EDIT: I also tried entering "int?" as the DataType, but Visual Studio throws an error when I enter it, saying that "Column requires a valid DataType."

    Read the article

  • WinUSB failing on non-development computers

    - by Giawa
    Good afternoon, WinUSB is working well on the development computer that I am using (Win XP SP3). I am able to download new firmware to the Cypress FX2, and then connect to the new USB device once it 'renumerates'. However, if I've tried the same code with the WinUSB driver on a few other computers (Win XP SP3, Win7 x64) and they both returned the error "A device attached to the system is not functioning." when trying to use CreateFile to get a handle to the USB device. The devicePath was found successfully, so I'm not sure why it cannot connect to the device. Furthermore, the device manager states that my device is working properly. I'm curious if I'm missing something when compiling the code? I would guess that my development computer has something installed on it that the other computers do not? Or perhaps it's a power setting and the device is going to sleep (although I've fooled around with the Power Options on each computer to no avail). Does anyone have any ideas? I've compiled under Visual Studio 2008, and have installed the Microsoft C++ 2008 Redistributable Package on the computers that I've tested on. Thanks, Giawa

    Read the article

  • How To Correctly Specify A Default Value For A String Field In A PHP/MySQL Prepared Statement

    - by Joshua
    I'm trying to debug some auto-generated code, but I am a mySQL noob. Everything goes fine ultil the "prepare" line below, and then for some reason $mysqli_stmt is false, yielding the stated error. Could it have something to do with the SQL_MODE = 'ANSI'? The failure seems to have something to do with the string 'xxx' below, but it still happens no matter what I change it to. This value is meant to be a default value for the TickerDigest field, but strangely if I change 'xxx' to 'c_u_TickerDigest', then it suddenly works, but the TickerDigest field is inserted as 'null' when I look in the database. $mysqli = mysqli_init(); $mysqli->options(MYSQLI_INIT_COMMAND, "SET SQL_MODE = 'ANSI'"); $mysqli->real_connect(SR_Host,SR_Username,SR_Password,SR_Database) or die('Unable to connect to Database'); $sql_stmt = 'INSERT INTO "t_sr_u_Product"("c_u_Name", "c_u_Code", "c_u_TickerDigest") VALUES (?, ?, "xxx")'; $mysqli_stmt = $mysqli->prepare($sql_stmt); Fatal error: Uncaught exception 'Exception' with message 'INSERT INTO "t_sr_u_Product"("c_u_Name", "c_u_Code", "c_u_TickerDigest") VALUES (?, ?, "xxx"): prepare statement failed: Unknown column 'xxx' in 'field list'' in P:\StarRise\SandBox\GateKeeper\Rise\srIProduct.php on line 18 I'm hopeful what's going wrong is fairly simple, since I'm almost completely ignorant about SQL.

    Read the article

  • How do I become better in math, after being a programmer for several years.

    - by loxs
    I've had quite a weird career till now. First I graduated from a medical school. Then I went into marketing (pharmaceuticals). And then umm, after some time, I decided to go for my (till then) hobby and became a "professional" programmer. I've been quite successful at this ever since. I have quite some languages "under my belt". I earn not bad and I have been involved in the opensource community quite heavily. The thing is that I suck at math :). Well, not totally of course, as I get my work done. But I don't know how much I suck. And I don't know how to find out. Math has never really been of any priority during my middle/high school years. I only picked as little as I could afford, because I was always getting ready to go for Medicine. Of course I know the basics of algebra. Things like "normal" and square equations. Also the basics of geometry. But well, there are things that I have missed. And lately I am being fascinated by things like probability theory, infinity, chaos/order etc. But every time I try to learn something about these topics, I hit a wall of terminology, special symbols, and some special kind of thinking, that is quite like mine (a programmer), but also a lot different (and appears weird to me). So, what kinds of books would you recommend me? It's very hard to find something suitable. All that I find are either too easy (and boring) or totally impenetrable.

    Read the article

  • Using git svn with some awkward permissions

    - by Migs
    Due to some funky permissions on our client's side that we can't change, we have a project whose hierarchy looks something like: projectname/trunk: foo/, bar/, baz/ projectname/branches: branch1/, branch2/ (where branch1 and branch2 each contain foo, bar, and baz.) The thing is, I have no permission to access trunk, so I can't just do a clone of project/trunk. I do have permission to access branches. What I am currently doing is checking out each subdirectory individually via git svn clone, so that each one has their own git repo. I use a script to update/commit them all, but what I would prefer to do is to check them all out under a single repo, and be able to commit changes with a single call to git svn dcommit. Is this possible? I mentioned the branches hierarchy because if possible, I'd also like to be able to track the branches the way I could if the permissions were more sane. I've tried permuting a lot of options that sounded useful, but I haven't found one that gives me exactly what I want. I sense that the solution may have something to do with --no-minimize-url, but I'm not even sure about that, as it didn't help me when I tried it.

    Read the article

  • How to force my method to accept objects from external software?

    - by Roman
    I have a method which needs to take a callback object as an argument and then (at the moment when it's needed) my method will call a specific method of the callback object. I wrote a class called Manager which has a method called addListener. As the argument for this method I need to use a callback object which is defined by the external software. So, I define the addListener in the following way: public void addListener(Listener listener). Of course Eclipse complains because it does not know what Listener is (because the Listener is defined by the external software). The only think that I know (should know) about the Listener is that it has a method called doSomething. So, to pleasure Eclipse I add an interface before my Manager class: interface Listener { void doSomething(); } public class CTManager { ... The problem seems to be solved but then I try to test my software. So, I create a class called test. In this class I create an instance of the Manager class and try to use addListener method of this instance. I also create a class Listener, instantiate it and give the instance to the addListener. And it's the place where the problem appears. Eclipse writes that addListener is not applicable to the given argument. I think it's because it expect something from my Listenr interface but gets something from the Listener class. How can I solve this problem?

    Read the article

  • Returning a reference from a Class member?

    - by nebukadnezzar
    Hi, I've a class that basically looks like this: class App { public function newTemplate($filename, $vars=array()) { $smarty = new Smarty; $smarty->compile_dir = $this->template_compile_path; if(count($vars) > 0) { foreach($vars as $v_key => $v_name) { $smarty->assign($v_key, $v_name); } } return $smarty; } } However, when I create a Instance of 'App', the reference to $smarty seems broken, as every call to the membermethods don't seem to do anything: $app = new App; $tpl = $app->newTemplate("index.tmpl"); $tpl->assign("foo", "bar"); // {$foo} does not appear with "bar" in the template Now I wonder why? Of course I tried to use references: ... public function &newTemplate() ... ... But that doesn't work. Variable references don't seem to work either: ... $tpl = &$app->newTemplate("index.tmpl"); ... What is causing PHP here not to return a proper reference? Help is very appreciated!

    Read the article

  • WPF Event Handler in Another Class

    - by Nathan Tornquist
    I have built a series of event handlers for some custom WPF controls. The event handles format the text displayed when the user enters or leaves a textbox based on the type of data contained (Phone number, zip code, monetary value, etc.) Right now I have all of the events locally in the C# code directly attached to the xaml. Because I have developed a could controls, this means that the logic is repeated a lot, and if I want to change the program-wide functionality I would have to make changes everywhere the event code is located. I am sure there is a way to put all of my event handlers in a single class. Can anyone help point me in the correct direction? I saw this article: Event Handler located in different class than MainWindow But I'm not sure if it directly relates to what I'm doing. I would rather make small changes to the existing logic that I have, as it works, then rewrite everything into commands. I would essentially like to something like this if possible: LostFocus="ExpandedTextBoxEvents.TextBox_LostFocus" It is easy enough to do something like this: private void TextBoxCurrencyGotFocus(object sender, RoutedEventArgs e) { ExpandedTextBoxEvents.TextBoxCurrencyGotFocus(sender, e); } private void TextBoxCurrencyLostFocus(object sender, RoutedEventArgs e) { ExpandedTextBoxEvents.TextBoxCurrencyLostFocus(sender, e); } But that is less elegant.

    Read the article

  • session variables in an ASP.NET

    - by Beep
    hi guy i am trying to place my session in to a drop down, any help would be great. at the moment it puts the data in to a label, i wish to put it into a dropdown with it adding a new string every time i click button without getting rid of the last default page protected void Button1_Click1(object sender, EventArgs e) { Session["Fruitname"] = TbxName.Text; // my session i have made } output page protected void Page_Load(object sender, EventArgs e) { var fruitname = Session["Fruitname"] as String; // my session ive made fruit.Text = fruitname; // session used in lable } Have Tried var myFruits = Session["Fruitname"] as List<string>; myFruits.Add(listbox1.Text); but i get error when i try to run the program Broken glass thanks for your help, it is still not doing what i need but its getting there. var fruitname = Session["Fruitname"] as String; // my session ive made fruit.Text = string.Join(",", fruitname); // session used in lable this is what is working. i need a dropdown to display all the strings put into TbxName.Text; to output into fruit

    Read the article

  • Unit Testing - Algorithm or Sample based ?

    - by ohadsc
    Say I'm trying to test a simple Set class public IntSet : IEnumerable<int> { Add(int i) {...} //IEnumerable implementation... } And suppose I'm trying to test that no duplicate values can exist in the set. My first option is to insert some sample data into the set, and test for duplicates using my knowledge of the data I used, for example: //OPTION 1 void InsertDuplicateValues_OnlyOneInstancePerValueShouldBeInTheSet() { var set = new IntSet(); //3 will be added 3 times var values = new List<int> {1, 2, 3, 3, 3, 4, 5}; foreach (int i in values) set.Add(i); //I know 3 is the only candidate to appear multiple times int counter = 0; foreach (int i in set) if (i == 3) counter++; Assert.AreEqual(1, counter); } My second option is to test for my condition generically: //OPTION 2 void InsertDuplicateValues_OnlyOneInstancePerValueShouldBeInTheSet() { var set = new IntSet(); //The following could even be a list of random numbers with a duplicate var values = new List<int> { 1, 2, 3, 3, 3, 4, 5}; foreach (int i in values) set.Add(i); //I am not using my prior knowledge of the sample data //the following line would work for any data CollectionAssert.AreEquivalent(new HashSet<int>(values), set); } Of course, in this example, I conveniently have a set implementation to check against, as well as code to compare collections (CollectionAssert). But what if I didn't have either ? This is the situation when you are testing your real life custom business logic. Granted, testing for expected conditions generically covers more cases - but it becomes very similar to implementing the logic again (which is both tedious and useless - you can't use the same code to check itself!). Basically I'm asking whether my tests should look like "insert 1, 2, 3 then check something about 3" or "insert 1, 2, 3 and check for something in general" EDIT - To help me understand, please state in your answer if you prefer OPTION 1 or OPTION 2 (or neither, or that it depends on the case, etc )

    Read the article

  • c++ specialized overload?

    - by acidzombie24
    -edit- i am trying to close the question. i solved the problem with boost::is_base_and_derived In my class i want to do two things. 1) Copy int, floats and other normal values 2) Copy structs that supply a special copy function (template T copyAs(); } the struct MUST NOT return int's unless i explicitly say ints. I do not want the programmer mistaking the mistake by doing int a = thatClass; -edit- someone mention classes dont return anything, i mean using the operator Type() overload. How do i create my copy operator in such a way i can copy both 1) ints, floats etc and the the struct restricted in the way i mention in 2). i tried doing template <class T2> T operator = (const T2& v); which would cover my ints, floats etc. But how would it differentiate from structs? so i wrote T operator = (const SomeGenericBase& v); The idea was the GenericBase would be unsed instead then i can do v.Whatever. But that backfires bc the functions i want wouldnt exist, unless i use virtual, but virtual templates dont exist. Also i would hate to use virtual I think the solution is to get rid of ints and have it convert to something that can do .as(). So i wrote something up but now i have the same problem, how does that differentiate ints and structs that have the .as() function template?

    Read the article

  • How to store and locate multiple interface types within a Delphi TInterfaceList

    - by Brian Frost
    Hi, I'm storing small interfaces from a range of objects into a single TInterfaceList 'store' with the intention of offering list of specific interface types to the end user, so each interface will expose a 'GetName' function but all other methods are unique to that interface type. For example here are two interfaces: IBase = interface //---------------------------------------- function GetName : string; //---------------------------------------- end; IMeasureTemperature = interface(IBase) //------------------------------------ function MeasureTemperature : double; //---------------------------------------- end; IMeasureHumidity = interface(IBase) //---------------------------------------- function MeasureHumidity: double; //---------------------------------------- end; I put several of these interfaces into a single TInterfaceList and then I'd like to scan the list for a specific interface type (e.g. 'IMeasureTemperature') building another list of pointers to the objects exporting those interfaces. I wish to make no assumptions about the locations of those objects, some may export more than one type of interface. I know I could do this with a class hierarchy using something like: If FList[I] is TMeasureTemperature then .. but I'd like to do something simliar with an interface type, Is this possible?

    Read the article

  • programs hangs during socket interaction

    - by herrturtur
    I have two programs, sendfile.py and recvfile.py that are supposed to interact to send a file across the network. They communicate over TCP sockets. The communication is supposed to go something like this: sender =====filename=====> receiver sender <===== 'ok' ======= receiver or sender <===== 'no' ======= receiver if ok: sender ====== file ======> receiver I've got The sender and receiver code is here: Sender: import sys from jmm_sockets import * if len(sys.argv) != 4: print "Usage:", sys.argv[0], "<host> <port> <filename>" sys.exit(1) s = getClientSocket(sys.argv[1], int(sys.argv[2])) try: f = open(sys.argv[3]) except IOError, msg: print "couldn't open file" sys.exit(1) # send filename s.send(sys.argv[3]) # receive 'ok' buffer = None response = str() while 1: buffer = s.recv(1) if buffer == '': break else: response = response + buffer if response == 'ok': print 'receiver acknowledged receipt of filename' # send file s.send(f.read()) elif response == 'no': print "receiver doesn't want the file" # cleanup f.close() s.close() Receiver: from jmm_sockets import * s = getServerSocket(None, 16001) conn, addr = s.accept() buffer = None filename = str() # receive filename while 1: buffer = conn.recv(1) if buffer == '': break else: filename = filename + buffer print "sender wants to send", filename, "is that ok?" user_choice = raw_input("ok/no: ") if user_choice == 'ok': # send ok conn.send('ok') #receive file data = str() while 1: buffer = conn.recv(1) if buffer=='': break else: data = data + buffer print data else: conn.send('no') conn.close() I'm sure I'm missing something here in the sorts of a deadlock, but don't know what it is.

    Read the article

  • how to achieve functionality of #def of c in PHP

    - by Sabya
    Well, I don't know if thats what I want. But here is my problem: In case of some error I am logging the FILE, CLASS, FUNCTION and LINE in a file. For that I am doing something like: myLog('['. __FILE__ . ']' . '[' . __CLASS__ . ']' . '[' . __FUNCTION__ . ']' . '[' . __LINE__ . ']'); The problem is everywhere I've to repeat that code in the parameter. and If I want to change the format, I've to change everywhere. How can I have something like: myLog(LOG_MSG_FORMAT); With PHP define it is not possible since it will give my the LINE number of the place where that definition is, not where the definition is getting used. Any solution to this is welcome. I am not bitchy about having C like functionality of #def.

    Read the article

  • What does the Kernel Virtual Memory of each process contain?

    - by claws
    When say 3 programs (executables) are loaded into memory the layout might look something like this: I've following questions: Is the concept of Virtual Memory limited to user processes? Because, I am wondering where does the Operating System Kernel, Drivers live? How is its memory layout? I know its operating system specific make your choice (windows/linux). They say, on a 32 bit machine in a 4GB address space. Half of it (or more recently 1GB) is occupied by kernel. I can see in this diagram that "Kernel Virtual memory" is occupying 0xc0000000 - 0xffffffff (= 1 GB). Are they talking about this? or is it something else? Just want to confirm. What exactly does the Kernel Virtual Memory of each of these processes contain? What is its layout? When we do IPC we talk about shared memory. I don't see any memory shared between these processes. Where does it live? Resources (files, registries in windows) are global to all processes. So, the resource/file handle table must be in some global space. Which area would that be in? Where can I know more about this kernel side stuff.

    Read the article

  • How do I use the Enum value from a class in another part of code?

    - by ChiggenWingz
    Coming from a C# background from a night course at a local college, I've sort of started my way in C++. Having a lot pain getting use to the syntax. I'm also still very green when it comes to coding techniques. From my WinMain function, I want to be able to access a variable which is using an enum I declared in another class. (inside core.h) class Core { public: enum GAME_MODE { INIT, MENUS, GAMEPLAY }; GAME_MODE gameMode; Core(); ~Core(); ...OtherFunctions(); }; (inside main.cpp) Core core; int WINAPI WinMain(...) { ... startup code here... core.gameMode = Core.GAME_MODE.INIT; ...etc... } Basically I want to set that gameMode to the enum value of Init or something like that from my WinMain function. I want to also be able to read it from other areas. I get the error... expected primary-expression before '.' token If I try to use core.gameMode = Core::GAME_MODE.INIT;, then I get the same error. I'm not fussed about best practices, as I'm just trying to get the basic understanding of passing around variables in C++ between files. I'll be making sure variables are protected and neatly tucked away later on once I am use to the flexibility of the syntax. If I remember correctly, C# allowed me to use Enums from other classes, and all I had to do was something like Core.ENUMNAME.ENUMVALUE. I hope what I'm wanting to do is clear :\ As I have no idea what a lot of the correct terminology is.

    Read the article

  • My Rails session is getting reset when I have concurrent requests

    - by alex_c
    I think I might be misunderstanding something about Rails sessions, so please bear with me, I might not be phrasing my question the best way. I'm working on an iPhone app with a Ruby on Rails backend. I have a web view which by default goes to the index action of one controller (and uses sessions), and in the background a bunch of API calls going to a different controller (and which don't need to use sessions). The problem is, the sessions set by my web view seem to be overwitten by the API calls. My staging server is pretty slow, so there's lots of time for the requests to overlap each other - what I see in the logs is basically this: Request A (first controller) starts. Session is empty. Request B (second controller) starts. Session is empty. Request A finishes. Request A has done authentication, and stored the user ID in the session. Session contains user ID. Request B finishes. Session is empty. Request C starts. Session is empty - not what I want. Now, the strange thing is that request B should NOT be writing anything to the session. I do have before and after filters which READ from the session - things like: user = User.find_by_id(session[:id]) or logger.debug session.inspect and if I remove all of those, then everything works as expected - session contents get set by request A, and they're still there when request C starts. So. I think I'm missing something about how sessions work. Why would reading from the session overwrite it? Should I be accessing it some other way? Am I completely on the wrong track and the problem is elsewhere? Thank you for any insights!

    Read the article

< Previous Page | 445 446 447 448 449 450 451 452 453 454 455 456  | Next Page >