DISCLAIMER: I haven't done C++ for some time... Is it common nowadays to decorate C/C++ function/method declarations in order to improve readability? Crude Example: void some_function(IN int param1, OUT char **param2); with the macros IN and OUT defined with an empty body (i.e. lightweight documentation if you will in this example). ...
If you create a new ATL project and add a simple COM object to it (note: an object and not a control) that uses the Apartment threading model, will there be a message pump running under the hood? I want to create a hidden window that is a member of my COM object class but I'm not sure if any messages will actually be delivered to it or ...
I recently discovered that the implementation of the hash map in c++ will be called unordered_map. When I looked up why they weren't just using hash_map, I discovered that apparently there are compatiblity issues with the implementation of hash_map that unordered_map resolves(http://en.wikipedia.org/wiki/Unordered_map_%28C%2B%2B%29). The...
I'm investigating a deadlock bug. I took a core with gcore, and found that one of my functions seems to have called itself - even though it does not make a recursive function call. Here's a fragment of the stack from gdb: Thread 18 (Thread 4035926944 (LWP 23449)): #0 0xffffe410 in __kernel_vsyscall () #1 0x005133de in __lll_mutex_loc...
Im tryin to implement a push front method to a C++ double ended queue. The way that i did it was shifting each element of the array. It worked, but my program crashes at the end! In my push front method I seem to be "running past the end of my array", resulting in a heap corruption error, debug assertion, those things.. I havent been ab...
As mentioned in the docs what do i need to install to run the commands : bootstrap .\bjam The BoostPro Computing folks maintain the Boost installer for Windows, but if I first run the installer and download a minimal build and then run the installer again, the installer doesn't detect that I've already installed Boost already and I ...
I'm not sure what could be causing this. ==18270== Invalid free() / delete / delete[] ==18270== at 0x400576A: operator delete(void*) (vg_replace_malloc.c:342) ==18270== by 0x80537F7: LCD::LCDControl::~LCDControl() (LCDControl.cpp:23) ==18270== by 0x806C055: main (Main.cpp:22) ==18270== Address 0x59e92c4 is 388 bytes inside a b...
I am new to boost - can you please tell me what are the difference b/w the following variations of the boost lib and which one do I need to link to in which case? libboost_unit_test_framework-vc80-1_35.lib libboost_unit_test_framework-vc80-gd-1_35.lib libboost_unit_test_framework-vc80-mt-1_35.lib libboost_unit_test_framework-vc80-mt-...
This class: template <class T> struct A { A() : t(T()) { } A(const T& t_) : t(t_) { } T t; }; won't compile if T doesn't have default constructor. This one: template <class T> struct A { A(const T& t_) : t(t_) { } T t; }; won't have default constructor even if T has default constructor. I want to have both - If...
Hello, The code below is my own implementation a push_front method for my items array. I was wondering if someone could help me figure out how to implement the method so that i am just moving the indexes up or down. I need my items to stay in the array, rather then dumping them into a "front" varaible: stack::stack(int capacity) : item...
Say I wanted to have one variable in a class always be in some relation to another without changing the "linked" variable explicitly. For example: int foo is always 10 less than int bar. Making it so that if I changed bar, foo would be changed as well. Is there a way to do this? (Integer overflow isn't really possible so don't worry ab...
Does anyone know why the STL containers don't have virtual destructors? As far as I can tell, the only benefits are: it reduces the size of an instance by one pointer (to the virtual method table) and it makes destruction and construction a tiny bit faster. The downside is that it's unsafe to subclass the containers in the usua...
I've run into some annoying issues with const-correctness in some templated code, that ultimately boils down to the following observation: for some reason, given an STL-ish Container type T, const typename T::pointer does not actually seem to yeild a constant pointer type, even if T::pointer is equivalent to T::value_type*. The followin...
What is the difference between passing-by-reference and using the C pointer notation? void some_function(some_type& param) and void some_function(some_type *param) Thanks ...
I'm having a QT/C++ problem with a simple QWidget program that draws an ellipse inside a child QWidget. The program is composed of: (1) A parent QWidget (2) A child QWidget (used as the drawing surface for an ellipse) (3) A draw QPushButton Here is part of the code (QPushButton Slot and Signal code omitted for simplicity) void Draw::...
I downloaded the latest open source version of QT4-and its installed in c:\qt\2009.04. I've also downloaded the QT4 Visual Studio add-in 1.1.0. I want to set it up for both Visual Studio 2005 and Visual Studio 2008 . Most of the docs online are for older versions. What steps do I follow? ...
I want to open a file for reading. However, in the context of this program, it's OK if the file doesn't exist, I just move on. I want to be able to identify when the error is "file not found" and when the error is otherwise. Otherwise means I need to quit and error. I don't see an obvious way to do this with fstream. I can do this wi...
I have a pointer to a QScriptEngine that I'm passing through the overloaded class constructor of class Evaluator and assigns it to QScriptEngine *engine_ (class Property subclasses Evaluator, and calls this constructor of Evaluator, passing it an already allocated QScriptEngine). The constructor with no arguments creates the new QScriptE...
I am crafting a small project in mixed C and C++. I am building one small-ish state-machine at the heart of one of my worker thread. I was wondering if you gurus on SO would share your state-machine design techniques. NOTE: I am primarily after tried & tested implementation techniques. UPDATED: Based on all the great input gathered o...
I know that if I do something like this: class Obj { public: int* nine; }; Obj Obj1; //Awesome name int eight = 8; Obj1.nine = &eight; Obj Obj2 = Obj1; //Another Awesome name then Obj1's and Obj2's nines will point to the same 8, but will they share the same pointer? I.e.: int Necronine = 9; Obj1.nine = &Necronine; Obj2.nine == ...