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  • PDCurses TUI with C++ Win32 console application

    - by Bach
    I have downloaded pdcurses source and was able to successfully include curses.h in my project, linked the pre-compiled library and all good. After few hours of trying out the library, I saw the tuidemo.c in the demos folder, compiled it into an executable and brilliant! exactly what I needed for my project. Now the problem is that it's a C code, and I am working on a C++ project in VS c++ 2008. The files I need are tui.c and tui.h How can I include that C file in my C++ code? I saw few suggestions here but the compiler was not too happy with 100's of warnings and errors. How can I go on including/using that TUI pdcurses includes!? Thanks EDIT: I added extern "C" statement, so my test looks like this now, but I'm getting some other type of error #include <stdio.h> #include <stdlib.h> using namespace std; extern "C" { #include <tui.h> } void sub0(void) { //do nothing } void sub1(void) { //do nothing } int main (int argc, char * const argv[]) { menu MainMenu[] = { { "Asub", sub0, "Go inside first submenu" }, { "Bsub", sub1, "Go inside second submenu" }, { "", (FUNC)0, "" } /* always add this as the last item! */ }; startmenu(MainMenu, "TUI - 'textual user interface' demonstration program"); return 0; } Although it is compiling successfully, it is throwing an Error at runtime: 0xC0000005: Access violation reading location 0x021c52f9 at line startmenu(MainMenu, "TUI - 'textual user interface' demonstration program"); Not sure where to go from here. thanks again.

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  • Accessing Members of Containing Objects from Contained Objects.

    - by Bunkai.Satori
    If I have several levels of object containment (one object defines and instantiates another object which define and instantiate another object..), is it possible to get access to upper, containing - object variables and functions, please? Example: class CObjectOne { public: CObjectOne::CObjectOne() { Create(); }; void Create(); std::vector<ObjectTwo>vObejctsTwo; int nVariableOne; } bool CObjectOne::Create() { CObjectTwo ObjectTwo(this); vObjectsTwo.push_back(ObjectTwo); } class CObjectTwo { public: CObjectTwo::CObjectTwo(CObjectOne* pObject) { pObjectOne = pObject; Create(); }; void Create(); CObjectOne* GetObjectOne(){return pObjectOne;}; std::vector<CObjectTrhee>vObjectsTrhee; CObjectOne* pObjectOne; int nVariableTwo; } bool CObjectTwo::Create() { CObjectThree ObjectThree(this); vObjectsThree.push_back(ObjectThree); } class CObjectThree { public: CObjectThree::CObjectThree(CObjectTwo* pObject) { pObjectTwo = pObject; Create(); }; void Create(); CObjectTwo* GetObjectTwo(){return pObjectTwo;}; std::vector<CObjectsFour>vObjectsFour; CObjectTwo* pObjectTwo; int nVariableThree; } bool CObjectThree::Create() { CObjectFour ObjectFour(this); vObjectsFour.push_back(ObjectFour); } main() { CObjectOne myObject1; } Say, that from within CObjectThree I need to access nVariableOne in CObjectOne. I would like to do it as follows: int nValue = vObjectThree[index].GetObjectTwo()->GetObjectOne()->nVariable1; However, after compiling and running my application, I get Memory Access Violation error. What is wrong with the code above(it is example, and might contain spelling mistakes)? Do I have to create the objects dynamically instead of statically? Is there any other way how to achieve variables stored in containing objects from withing contained objects?

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  • Impossible to remove directory

    - by Mark
    Evidently I've never had to delete a directory using win32 sdk before, because its apparently an impossible task. I've tried anything and everything - RemoveDirectory, SHFileOperation with FO_DELETE, etc. Currently I call CreateDirectory in one thread, start another thread, copy some files to this directory in the new thread, then delete all the files in the directory in the new thread, and then back in the original thread that created the directory, try to delete the now empty directory and it fails. The directory really and truly is empty when I try to delete it, but it makes no difference. The whole thread aspect is irrelevant I think because at one point everything was in one thread and it didn't work. I'm currently setting a SecurityAttributes structure on CreateDirectory to grant access to everyone, but it makes no difference. RemoveDirectory in the past has returned '32' on GetLastError, which I believe is Sharing violation. But even if I just try to delete the empty directory from the command line, it refuses saying, "The process cannot access the file because it is being used by another process." until I shut down the entire application that created the directory. (Note: the directory is created in GetTempPath.)

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  • C++ Beginner Delete Question

    - by Pooch
    Hi all, This is my first year learning C++ so bear with me. I am attempting to dynamically allocate memory to the heap and then delete the allocated memory. Below is the code that is giving me a hard time: // String.cpp #include "String.h" String::String() {} String::String(char* source) { this->Size = this->GetSize(source); this->CharArray = new char[this->Size + 1]; int i = 0; for (; i < this->Size; i++) this->CharArray[i] = source[i]; this->CharArray[i] = '\0'; } int String::GetSize(const char * source) { int i = 0; for (; source[i] != '\0'; i++); return i; } String::~String() { delete[] this->CharArray; } Here is the error I get when the compiler tries to delete the CharArray: 0xC0000005: Access violation reading location 0xccccccc0. And here is the last call on the stack: msvcr100d.dll!operator delete(void * pUserData) Line 52 + 0x3 bytes C++ I am fairly certain the error exists within this piece of code but will provide you with any other information needed. Oh yeah, using VS 2010 for XP. Thanks for any and all help!

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  • C++ destructos causing crash's

    - by larsonator
    ok, so i got a some what intricate program that simulates the uni systems of students, units, and students enrolling in units. Students are stored in a binary search tree, Units are stored in a standard list. Student has a list of Unit Pointers, to store which units he/she is enrolled in Unit has a list of Student pointers, to store students which are enrolled in that unit. The unit collections (storing units in a list) as made as a static variable where the main function is, as is the Binary search tree of students. when its finaly time to close the program, i call the destructors of each. but at some stage, during the destructors on the unit side, Unhandled exception at 0x002e4200 in ClassAllocation.exe: 0xC0000005: Access violation reading location 0x00000000. UnitCollection destructor: UnitCol::~UnitCol() { list<Unit>::iterator itr; for(itr = UnitCollection.begin(); itr != UnitCollection.end();) { UnitCollection.pop_front(); itr = UnitCollection.begin(); } } Unit Destructor Unit::~Unit() { } now i got the same sorta problem on the student side of things BST destructors void StudentCol::Destructor(const BTreeNode * r) { if(r!= 0) { Destructor(r->getLChild()); Destructor(r->getRChild()); delete r; } } StudentCol::~StudentCol() { Destructor(root); } Student Destructor Student::~Student() { } so yeah any help would be greatly appreciated

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  • Add webservice reference, the classes in different file

    - by ArunDhaJ
    Hi, When I add webservice as service reference in my .Net project, it creates a service folder within "Service References". All the interfaces and classes are contained within that service folder. I wanted to know how to split the interface's method and classes. Actually I wanted the web service reference to import classes defined in different dll. I wanted to define this way because of my design constraints. I've 3 layered application. Of which third layer is communication layer which holds all web service references. second is business layer and first is presentation layer. If the class declarations are in layer-3 and I'm accessing those classes from presentation layer, it is logically a cross-layer-access-violation. Instead, I wanted a separate project which holds only the class declarations and this would be used in all 3 layers. I didn't faced any problems to achieve this with layer-1 and layer-2. But, I'm not sure how to make communication layer to use this common declaration dll. Your suggestion would help me to design my application better. Thanks in advance Regards ArunDhaJ

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  • How are declared private ivars different from synthesized ivars?

    - by lemnar
    I know that the modern Objective-C runtime can synthesize ivars. I thought that synthesized ivars behaved exactly like declared ivars that are marked @private, but they don't. As a result, come code compiles only under the modern runtime that I expected would work on either. For example, a superclass: @interface A : NSObject { #if !__OBJC2__ @private NSString *_c; #endif } @property (nonatomic, copy) NSString *d; @end @implementation A @synthesize d=_c; - (void)dealloc { [_c release]; [super dealloc]; } @end and a subclass: @interface B : A { #if !__OBJC2__ @private NSString *_c; #endif } @property (nonatomic, copy) NSString *e; @end @implementation B @synthesize e=_c; - (void)dealloc { [_c release]; [super dealloc]; } @end A subclass can't have a declared ivar with the same name as one of its superclass's declared ivars, even if the superclass's ivar is private. This seems to me like a violation of the meaning of @private, since the subclass is affected by the superclass's choice of something private. What I'm more concerned about, however, is how should I think about synthesized ivars. I thought they acted like declared private ivars, but without the fragile base class problem. Maybe that's right, and I just don't understand the fragile base class problem. Why does the above code compile only in the modern runtime? Does the fragile base class problem exist when all superclass instance variables are private?

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  • How is it legal to reference an undefined type inside a structure?

    - by paxdiablo
    As part of answering another question, I came across a piece of code like this, which gcc compiles without complaint. typedef struct { struct xyz *z; } xyz; int main (void) { return 0; } This is the means I've always used to construct types that point to themselves (e.g., linked lists) but I've always thought you had to name the struct so you could use self-reference. In other words, you couldn't use xyz *z within the structure because the typedef is not yet complete at that point. But this particular sample does not name the structure and it still compiles. I thought originally there was some black magic going on in the compiler that automatically translated the above code because the structure and typedef names were the same. But this little beauty works as well: typedef struct { struct NOTHING_LIKE_xyz *z; } xyz; What am I missing here? This seems a clear violation since there is no struct NOTHING_LIKE_xyz type defined anywhere. When I change it from a pointer to an actual type, I get the expected error: typedef struct { struct NOTHING_LIKE_xyz z; } xyz; qqq.c:2: error: field `z' has incomplete type Also, when I remove the struct, I get an error (parse error before "NOTHING ...). Is this allowed in ISO C?

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  • Linux C debugging library to detect memory corruptions

    - by calandoa
    When working sometimes ago on an embedded system with a simple MMU, I used to program dynamically this MMU to detect memory corruptions. For instance, at some moment at runtime, the foo variable was overwritten with some unexpected data (probably by a dangling pointer or whatever). So I added the additional debugging code : at init, the memory used by foo was indicated as a forbidden region to the MMU; each time foo was accessed on purpose, access to the region was allowed just before then forbidden just after; a MMU irq handler was added to dump the master and the address responsible of the violation. This was actually some kind of watchpoint, but directly self-handled by the code itself. Now, I would like to reuse the same trick, but on a x86 platform. The problem is that I am very far from understanding how is working the MMU on this platform, and how it is used by Linux, but I wonder if any library/tool/system call already exist to deal with this problem. Note that I am aware that various tools exist like Valgrind or GDB to manage memory problems, but as far as I know, none of these tools car be dynamically reconfigured by the debugged code. I am mainly interested for user space under Linux, but any info on kernel mode or under Windows is also welcome!

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  • No Hibernate Exception on the same insert of data

    - by Mark Estrada
    Hi All, Hibernate Newbie here. I am quite unsure why I am not getting any exception when I am executing below code. On first attempt, this code creates the Book Entry on my Book Table. But my concern is that when I execute below code again, no error was pop out by Hibernate. I was in fact expecting some sort of Violation of Primary Key Constraints as what I have bee doing in JDBC code. public class BookDao { public void createBook(Book bookObj) { Session session = HibernateUtil.getSessionFactory() .getCurrentSession(); session.beginTransaction(); session.saveOrUpdate(bookObj); session.getTransaction().commit(); } } public class HibernateUtil { private static final SessionFactory sessionFactory = buildSessionFactory(); private static SessionFactory buildSessionFactory() { try { // Create the SessionFactory from hibernate.cfg.xml return new AnnotationConfiguration().configure() .buildSessionFactory(); } catch (Throwable ex) { // Make sure you log the exception, as it might be swallowed ex.printStackTrace(); throw new ExceptionInInitializerError(ex); } } public static SessionFactory getSessionFactory() { return sessionFactory; } } public class BookDBStarter { public static void main(String[] args) { Book bookHF = new Book(); bookHF.setIsbn("HF-12345"); bookHF.setName("Head First HTML"); bookHF.setPublishDate(new Date()); BookDao daoBook = new BookDao(); daoBook.createBook(bookHF); } } Is this normal hibernate way? And how will I know if my insert is successful? Any thoughts?

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  • C++ destructors causing crash's

    - by larsonator
    ok, so i got a some what intricate program that simulates the uni systems of students, units, and students enrolling in units. Students are stored in a binary search tree, Units are stored in a standard list. Student has a list of Unit Pointers, to store which units he/she is enrolled in Unit has a list of Student pointers, to store students which are enrolled in that unit. The unit collections (storing units in a list) as made as a static variable where the main function is, as is the Binary search tree of students. when its finaly time to close the program, i call the destructors of each. but at some stage, during the destructors on the unit side, Unhandled exception at 0x002e4200 in ClassAllocation.exe: 0xC0000005: Access violation reading location 0x00000000. UnitCollection destructor: UnitCol::~UnitCol() { list<Unit>::iterator itr; for(itr = UnitCollection.begin(); itr != UnitCollection.end();) { UnitCollection.pop_front(); itr = UnitCollection.begin(); } } Unit Destructor Unit::~Unit() { } now i got the same sorta problem on the student side of things BST destructors void StudentCol::Destructor(const BTreeNode * r) { if(r!= 0) { Destructor(r->getLChild()); Destructor(r->getRChild()); delete r; } } StudentCol::~StudentCol() { Destructor(root); } Student Destructor Student::~Student() { } so yeah any help would be greatly appreciated

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  • C++ VB6 interfacing problem

    - by Roshan
    Hi, I'm tearing my hair out trying to solve this one, any insights will be much appreciated: I have a C++ exe which acquires data from some hardware in the main thread and processes it in another thread (thread 2). I use a c++ dll to supply some data processing functions which are called from thread 2. I have a requirement to make another set of data processing functions in VB6. I have thus created a VB6 dll, using the add-in vbAdvance to create a standard dll. When I call functions from within this VB6 dll from the main thread, everything works exactly as expected. When I call functions from this VB6 dll in thread 2, I get an access violation. I've traced the error to the CopyMemory command, it would seem that if this is used within the call from the main thread, it's fine but in a call from the process thread, it causes an exception. Why should this be so? As far as I understand, threads share the same address space. Here is the code from my VB dll Public Sub UserFunInterface(ByVal in1ptr As Long, ByVal out1ptr As Long, ByRef nsamples As Long) Dim myarray1() As Single Dim myarray2() As Single Dim i As Integer ReDim myarray1(0 To nsamples - 1) As Single ReDim myarray2(0 To nsamples - 1) As Single With tsa1din(0) ' defined as safearray1d in a global definitions module .cDims = 1 .cbElements = 4 .cElements = nsamples .pvData = in1ptr End With With tsa1dout .cDims = 1 .cbElements = 4 .cElements = nsamples .pvData = out1ptr End With CopyMemory ByVal VarPtrArray(myarray1), VarPtr(tsa1din(0)), 4 CopyMemory ByVal VarPtrArray(myarray2), VarPtr(tsa1dout), 4 For i = 0 To nsamples - 1 myarray2(i) = myarray1(i) * 2 Next i ZeroMemory ByVal VarPtrArray(myarray1), 4 ZeroMemory ByVal VarPtrArray(myarray2), 4 End Sub

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  • Visual Studio - Edit source code located in a database

    - by mfeingold
    I am building something similar to Server Explorer for Apache CouchDB. One of the things necessary is to be able to edit CouchDB view definitions which in CouchDB are JavaScript functions. How can I trick Visual Studio into using my object to retrieve and save the content of the JavaScript function but still use the rest of it - I am happy with editor itself and have no intention of writing my own Editor/Language Service, etc. The latter would be much bigger effort than what this project warrants Edit After more digging I am still stuck. Here is what I know: IVsUIShellOpenDocument interface provides a method OpenStandardEditor which can be used to open the standard Visual Studio editor. As one of the parameters this method takes a Pointer to the IUnknown interface of the document data object. This object is supposed to implement several interfaces described in many places all over the MSDN. Visual Studio SDK also provides a 'sample' implementation of the document data object VsTextBufferClass. I can create an instance of this class and when I pass the pointer to the instance to the OpenStandardEditor I can see my editor and it seems to work ok. When I try to implement my own class implementing the same interfaces (IVsTextBuffer, VsTextBuffer, IVsTextLines) OpenStandardEditor method returns success, but VS bombs out on call editor.Show() with an access violation. My suspicion is that VsTextBufferClass also implements some other interface(s) but not in C# way but rather in the good old COM way. I just do not know which one(s). Any thoughts?

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  • Why doesn't my test run tearDownAfterTestClass when it fails

    - by Memor-X
    in a test i am writing the setUpBeforeTests creates a new customer in the database who is then used to perform the tests with so naturally when i finish the test i should get rid of this test customer in tearDownAfterTestClass so that i can create then anew when i rerun the test and not get any false positives how when the tests all run fine i have no problem but if a test fails and i go to rerun it my setUpBeforeTests fails because i check for mysql errors in it like this try { if(!mysqli_query($connection,$query)) { $this->assertTrue(false); } } catch (Exception $exc) { $msg = '[tearDownAfterTestClass] Exception Error' . PHP_EOL . PHP_EOL; $msg .= 'Could not run query - '.mysqli_error($connection). PHP_EOL;; $this->fail($msg); } the error i get is that there is a primary key violation which is expected cause i'm trying to create a new customer using the same data (primary key is on email which is also used to log in) however that means when the test failed it didn't run tearDownAfterTestClass now i could just move everything in tearDownAfterTestClass to the start of setUpBeforeTests however to me that seems like bad programming since it defeates the purpose of even have tearDownAfterTestClass so i am wondering, why isn't my tearDownAfterTestClass running when a test fails NOTE: the database is a fundamental part of the system i'm testing and the database and system are on a separate development environment not the live one, the backup files for the database are almost 2 GBs and takes almost 1/2 an hour to restore, the purpose of the tear down is to remove any data we have added because of the test so that we don't have to restore the database every time we run the tests

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  • Create new or update existing entity at one go with JPA

    - by Alex R
    A have a JPA entity that has timestamp field and is distinguished by a complex identifier field. What I need is to update timestamp in an entity that has already been stored, otherwise create and store new entity with the current timestamp. As it turns out the task is not as simple as it seems from the first sight. The problem is that in concurrent environment I get nasty "Unique index or primary key violation" exception. Here's my code: // Load existing entity, if any. Entity e = entityManager.find(Entity.class, id); if (e == null) { // Could not find entity with the specified id in the database, so create new one. e = entityManager.merge(new Entity(id)); } // Set current time... e.setTimestamp(new Date()); // ...and finally save entity. entityManager.flush(); Please note that in this example entity identifier is not generated on insert, it is known in advance. When two or more of threads run this block of code in parallel, they may simultaneously get null from entityManager.find(Entity.class, id) method call, so they will attempt to save two or more entities at the same time, with the same identifier resulting in error. I think that there are few solutions to the problem. Sure I could synchronize this code block with a global lock to prevent concurrent access to the database, but would it be the most efficient way? Some databases support very handy MERGE statement that updates existing or creates new row if none exists. But I doubt that OpenJPA (JPA implementation of my choice) supports it. Event if JPA does not support SQL MERGE, I can always fall back to plain old JDBC and do whatever I want with the database. But I don't want to leave comfortable API and mess with hairy JDBC+SQL combination. There is a magic trick to fix it using standard JPA API only, but I don't know it yet. Please help.

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  • VSC++, virtual method at bad adress, curious bug

    - by antoon.groenewoud
    Hello, This guy: virtual phTreeClass* GetTreeClass() const { return (phTreeClass*)m_entity_class; } When called, crashed the program with an access violation, even after a full recompile. All member functions and virtual member functions had correct memory adresses (I hovered mouse over the methods in debug mode), but this function had a bad memory adress: 0xfffffffc. Everything looked okay: the 'this' pointer, and everything works fine up until this function call. This function is also pretty old and I didn't change it for a long time. The problem just suddenly popped up after some work, which I commented all out to see what was doing it, without any success. So I removed the virtual, compiled, and it works fine. I add virtual, compiled, and it still works fine! I basically changed nothing, and remember that I did do a full recompile earlier, and still had the error back then. I wasn't able to reproduce the problem. But now it is back. I didn't change anything. Removing virtual fixes the problem. Sincerely, Antoon

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  • SQL Server stored procedure return code oddity

    - by gbn
    Hello The client that calls this code is restricted and can only deal with return codes from stored procs. So, we modified our usual contract to RETURN -1 on error and default to RETURN 0 if no error If the code hits the inner catch block, then the RETURN code default to -4. Where does this come from, does anyone know...? IF OBJECT_ID('dbo.foo') IS NOT NULL DROP TABLE dbo.foo GO CREATE TABLE dbo.foo ( KeyCol char(12) NOT NULL, ValueCol xml NOT NULL, Comment varchar(1000) NULL, CONSTRAINT PK_foo PRIMARY KEY CLUSTERED (KeyCol) ) GO IF OBJECT_ID('dbo.bar') IS NOT NULL DROP PROCEDURE dbo.bar GO CREATE PROCEDURE dbo.bar @Key char(12), @Value xml, @Comment varchar(1000) AS SET NOCOUNT ON DECLARE @StartTranCount tinyint; BEGIN TRY SELECT @StartTranCount = @@TRANCOUNT; IF @StartTranCount = 0 BEGIN TRAN; BEGIN TRY --SELECT @StartTranCount = 'fish' INSERT dbo.foo (KeyCol, ValueCol, Comment) VALUES (@Key, @Value, @Comment); END TRY BEGIN CATCH IF ERROR_NUMBER() = 2627 --PK violation UPDATE dbo.foo SET ValueCol = @Value, Comment = @Comment WHERE KeyCol = @Key; ELSE RAISERROR ('Tits up', 16, 1); END CATCH IF @StartTranCount = 0 COMMIT TRAN; END TRY BEGIN CATCH IF @StartTranCount = 0 AND XACT_STATE() <> 0 ROLLBACK TRAN; RETURN -1 END CATCH --Without this, we'll send -4 if we hit the UPDATE CATCH block above --RETURN 0 GO --Run with RETURN 0 and fish line commented out DECLARE @rtn int EXEC @rtn = dbo.bar 'abcdefghijkl', '<foobar />', 'testing' SELECT @rtn; SELECT * FROM dbo.foo DECLARE @rtn int EXEC @rtn = dbo.bar 'abcdefghijkl', '<foobar2 />', 'testing2' --updated OK but we get @rtn = -4 SELECT @rtn; SELECT * FROM dbo.foo --uncomment fish line DECLARE @rtn int EXEC @rtn = dbo.bar 'abcdefghijkl', '<foobar />', 'testing' --Hit outer CATCH, @rtn = -1 as expected SELECT @rtn; SELECT * FROM dbo.foo

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  • How do I make VC++'s debugger break on exceptions?

    - by Mason Wheeler
    I'm trying to debug a problem in a DLL written in C that keeps causing access violations. I'm using Visual C++ 2008, but the code is straight C. I'm used to Delphi, where if an exception occurs while running under the debugger, the program will immediately break to the debugger and it will give you a chance to examine the program state. In Visual C++, though, all I get is a message in the Output tab: First-chance exception at blah blah blah: Access violation reading location 0x04410000. No breaks, nothing. It just goes and unwinds the stack until it's back in my Delphi EXE, which recognizes something's wrong and alerts me there, but by that point I've lost several layers of call stack and I don't know what's going on. I've tried other debugging techniques, but whatever it's doing is taking place deep within a nested loop inside a C macro that's getting called more than 500 times, and that's just a bit beyond my skill (or my patience) to trace through. I figure there has to be some way to get the "first-chance" exception to actually give me a "chance" to handle it. There's probably some "break immediately on first-chance exceptions" configuration setting I don't know about, but it doesn't seem to be all that discoverable. Does anyone know where it is and how to enable it?

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  • What algorithms compute directions from point A to point B on a map?

    - by A. Rex
    How do map providers (such as Google or Yahoo! Maps) suggest directions? I mean, they probably have real-world data in some form, certainly including distances but also perhaps things like driving speeds, presence of sidewalks, train schedules, etc. But suppose the data were in a simpler format, say a very large directed graph with edge weights reflecting distances. I want to be able to quickly compute directions from one arbitrary point to another. Sometimes these points will be close together (within one city) while sometimes they will be far apart (cross-country). Graph algorithms like Dijkstra's algorithm will not work because the graph is enormous. Luckily, heuristic algorithms like A* will probably work. However, our data is very structured, and perhaps some kind of tiered approach might work? (For example, store precomputed directions between certain "key" points far apart, as well as some local directions. Then directions for two far-away points will involve local directions to a key points, global directions to another key point, and then local directions again.) What algorithms are actually used in practice? PS. This question was motivated by finding quirks in online mapping directions. Contrary to the triangle inequality, sometimes Google Maps thinks that X-Z takes longer and is farther than using an intermediate point as in X-Y-Z. But maybe their walking directions optimize for another parameter, too? PPS. Here's another violation of the triangle inequality that suggests (to me) that they use some kind of tiered approach: X-Z versus X-Y-Z. The former seems to use prominent Boulevard de Sebastopol even though it's slightly out of the way. (Edit: this example doesn't work anymore, but did at the time of the original post. The one above still works as of early November 2009.)

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  • Can isdigit legitimately be locale dependent in C

    - by cdev
    In the section covering setlocale, the ANSI C standard states in a footnote that the only ctype.h functions whose behaviour is not affected by the current locale are isdigit and isxdigit. The Microsoft implementation of isdigit is locale dependent because, for example, in locales using code page 1250 isdigit only returns non-zero for characters in the range 0x30 ('0') - 0x39 ('9'), whereas in locales using code page 1252 isdigit also returns non-zero for the superscript digits 0xB2 ('²'), 0xB3 ('³') and 0xB9 ('¹'). Is Microsoft in violation of the C standard by making isdigit locale dependent? In this question I am primarily interested in C90, which Microsoft claims to conform to, rather than C99. Additional background: Microsoft's own documentation of setlocale incorrectly states that isdigit is unaffected by the LC_CTYPE part of the locale. The section of the C standard that covers the ctype.h functions contains some wording that I consider ambiguous: "The behavior of these functions is affected by the current locale. Those functions that have locale-specific aspects only when not in the "C" locale are noted below." I consider this ambiguous because it is unclear what it is trying to say about functions such as isdigit for which there are no notes about locale-specific aspects. It might be trying to say that such functions must be assumed to be locale dependent, in which case Microsoft's implementation of isdigit would be OK. (Except that the footnote I mentioned earlier seems to contradict this interpretation.)

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  • How to use a class's type as the type argument for an inherited collection property in C#

    - by Edelweiss Peimann
    I am trying to create a representation of various types of card that inherit from a generic card class and which all contain references to their owning decks. I tried re-declaring them, as suggested here, but it still won't convert to the specific card type. The code I currently have is as such: public class Deck<T> : List<T> where T : Card { void Shuffle() { throw new NotImplementedException("Shuffle not yet implemented."); } } public class Card { public Deck<Card> OwningDeck { get; set; } } public class FooCard : Card { public Deck<FooCard> OwningDeck { get { return (Deck<FooCard>)base.OwningDeck; } set { OwningDeck = value; } } } The compile-time error I am getting: Error 2 Cannot convert type 'Game.Cards.Deck' to 'Game.Cards.Deck' And a warning suggesting I use a new operator to specify that the hiding is intentional. Would doing so be a violation of convention? Is there a better way? My question to stackoverflow is this: Can what I am trying to do be done elegantly in the .NET type system? If so, can some examples be provided?

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  • ZeroMQ REQ/REP on ipc:// and concurrency

    - by Metiu
    I implemented a JSON-RPC server using a REQ/REP 0MQ ipc:// socket and I'm experiencing strange behavior which I suspect is due to the fact that the ipc:// underlying unix socket is not a real socket, but rather a single pipe. From the documentation, one has to enforce strict zmq_send()/zmq_recv() alternation, otherwise the out-of-order zmq_send() will return an error. However, I expected the enforcement to be per-client, not per-socket. Of course with a Unix socket there is just one pipeline from multiple clients to the server, so the server won't know who it is talking with. Two clients could zmq_send() simultaneously and the server would see this as an alternation violation. The sequence could be: ClientA: zmq_send() ClientB: zmq_send() : will it block until the other send/receive completes? will it return -1? (I suspect it will with ipc:// due to inherent low-level problems, but with TCP it could distinguish the two clients) ClientA: zmq_recv() ClientB: zmq_recv() so what about tcp:// sockets? Will it work concurrently? Should I use some other locking mechanism to work around this?

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  • How can I exclude words with apostrophes when reading into a table of strings?

    - by rearden
    ifstream fin; string temp; fin.open("engldict.txt"); if(fin.is_open()) { bool apos = false; while(!fin.eof()) { getline(fin, temp, '\n'); if(temp.length() > 2 && temp.length() < 7) { for(unsigned int i = 0; i < temp.length(); i++) { if(temp.c_str()[i] == '\'') apos = true; } if(!apos) dictionary.insert(temp); } } } This code gives me a runtime error: Unhandled exception at 0x00A50606 in Word Jumble.exe: 0xC0000005: Access violation reading location 0x00000014. and throws me a break point at: size_type size() const _NOEXCEPT { // return length of sequence return (this->_Mysize); } within the xstring header. This exception is thrown no matter what character I use, so long as it is present within the words I am reading in. I am aware that it is probably a super simple fix, but I just really need another set of eyes to see it. Thanks in advance.

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  • Symfony generating database from model

    - by Sergej Jevsejev
    Hello, I am having troubles generating a simple database form model. I am using: Doctrine on Symfony 1.4.4 MySQL Workbench 5.2.16 with Doctrine Export 0.4.2dev So my ERL Model is: http://img708.imageshack.us/img708/1716/tmg.png Genereted YAML file: --- detect_relations: true options: collate: utf8_unicode_ci charset: utf8 type: InnoDB Course: columns: id: type: integer(4) primary: true notnull: true autoincrement: true name: type: string(255) notnull: true keywords: type: string(255) notnull: true summary: type: clob(65535) notnull: true Lecture: columns: id: type: integer(4) primary: true notnull: true autoincrement: true course_id: type: integer(4) primary: true notnull: true name: type: string(255) notnull: true description: type: string(255) notnull: true url: type: string(255) relations: Course: class: Course local: course_id foreign: id foreignAlias: Lectures foreignType: many owningSide: true User: columns: id: type: integer(4) primary: true unique: true notnull: true autoincrement: true firstName: type: string(255) notnull: true lastName: type: string(255) notnull: true email: type: string(255) unique: true notnull: true designation: type: string(1024) personalHeadline: type: string(1024) shortBio: type: clob(65535) UserCourse: tableName: user_has_course columns: user_id: type: integer(4) primary: true notnull: true course_id: type: integer(4) primary: true notnull: true relations: User: class: User local: user_id foreign: id foreignAlias: UserCourses foreignType: many owningSide: true Course: class: Course local: course_id foreign: id foreignAlias: UserCourses foreignType: many owningSide: true And no matter what I try this error occurs after: symfony doctrine:build --all --no-confirmation SQLSTATE[42000]: Syntax error or access violation: 1072 Key column 'user_userid' doesn't exist in table. Failing Query: "ALTER TABLE user_has_course ADD CONSTRAINT user_has_course_user_userid_user_id FOREIGN KEY (user_userid) REFERENCES user(id)". Failing Query: ALTER TABLE user_has_course ADD CONSTRAINT user_has_cou rse_user_userid_user_id FOREIGN KEY (user_userid) REFERENCES user(id) Currently I am studying Symfony, and stuck with this error. Please help.

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  • Maven + SSDM Build and Runtime Environment Automation

    - by Randy
    Preface: My Company, like most, has several run-time environments and several release versions which themselves are composed of different versions of various jars. For example, let us consider release versions 1.1, 1.2, and 1.3 of Software X, which may be deployed to a developer computer, testing, or production. Software-x-1.1 is itself composed of jarA-0.9.1 and jarB-0.7.5, but software-x-1.3 is composed of jarA-1.7.31 and jarB-0.8.1. Currently we use Spring's PropertyPlaceholderConfigurer to configure run-time variables (such as database credentials), however, properties also change with release versions. We also use Maven 2 POM version 4 to specify which versions of our code need to be used. We place the version numbers of our jars as properties within profiles (dev,test,prod) inside of the parent pom and then reference those version numbers in all project poms. As of right now, we have no way to specify which project versions pertain to a given release other than the most current one. Moreover, we deploy our run-time configurations to the SSDM pickup which then configures and creates the services defined by the built versions of our software. -- Questions: Is there any procedure/tool we can use to build our product by merely providing the run-time environment and version number? IE "build 1.1 dev"? Is there anyway we can store the required jar versions for each release build? We are currently versioning all files, including the parent pom, but merely versioning the parent pom does not record which release version is pertinent to that parent pom. What else can we do to further automate the process of builds? For example, if we could manage run-time configurations within the parent pom that would be a step in the right direction, but that seems like a violation of scope. Any tool outside of our framework is inconceivable at this point, but not in the far future. Summary: How can we automate our build process to the fullest extent without being error prone?

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