c++

How do i return a template class from a template function?

How do i pull off something that would make the last commented line compile? How would i have to change this code to make it work? #include<iostream> using namespace std; template <int x> class someclass{ public: int size; int intarr[x]; someclass():size(x){} }; template<int x, int y> int somefunc(someclass<x> A, someclass<y>...

Where does the compiler store methods for C++ classes?

This is more a curiosity than anything else... Suppose I have a C++ class Kitty as follows: class Kitty { void Meow() { //Do stuff } } Does the compiler place the code for Meow() in every instance of Kitty? Obviously repeating the same code everywhere requires more memory. But on the other hand, branching to a re...

Mingling C++ classes with Objective C classes

I am using the iphone SDK and coding primarily in C++ while using parts of the SDK in obj-c. Is it possible to designate a C++ class in situations where an obj-c class is needed? For instance: 1) when setting delegates to obj-c objects. I cannot make a C++ class derive from a Delegate protocol so this and possibly other reasons prev...

Using concurrently 2 versions of boost

I'm using RHEL 5.3, which is shipped with gcc 4.1.2 and boost 1.33. There're some features I want, that are missing in the boost 1.33. Therefore the thought was to upgrade to fresh boost release 1.43. Is it possible to use concurrently some header-only library(s) from boost 1.43 and the rest from 1.33? For example I want to use unord...

How to solve this error that is shown on Windbg?

Hello, I've loaded a .exe and it gave this error: Microsoft (R) Windows Debugger Version 6.12.0002.633 X86 Copyright (c) Microsoft Corporation. All rights reserved. CommandLine: "C:\Users\Public\SoundLog\Code\Código Python\SoundLog\dist\SoundLog.exe" Symbol search path is: *** Invalid *** **********************************************...

Makefiles - Compile all .cpp files in src/ to .o's in obj/, then link to binary in /

So, my project directory looks like this: /project Makefile main /src main.cpp foo.cpp foo.h bar.cpp bar.h /obj main.o foo.o bar.o What I would like my makefile to do would be to compile all .cpp files in the /src folder to .o files in the /obj folder, the...

How to fix this exception shown in windbg execution?

Hello, after running the .exe thought WinDBG, this was the exception information provided by pressing "k" when the exception occured: ChildEBP RetAddr 0012e2f4 6f9fbb1c KERNELBASE!RaiseException+0x58 0012e354 6fba88f4 mscorwks!RaiseTheExceptionInternalOnly+0x2a8 0012e36c 6fba8966 mscorwks!RaiseTheException+0x4e 0012e394 6fba8997 msco...

Compilation problem in the standard x86_64 libraries

Hi everyone, I am having trouble compiling a program I have written. I have two different files with the same includes but only one generates the following error when compiled with g++ /usr/lib/gcc/x86_64-linux-gnu/4.4.1/../../../../lib/crt1.o: In function `_start': /build/buildd/eglibc-2.10.1/csu/../sysdeps/x86_64/elf/start.S:109: und...

why no implicit conversion from pointer to reference to const pointer.

I'll illustrate my question with code: #include <iostream> void PrintInt(const unsigned char*& ptr) { int data = 0; ::memcpy(&data, ptr, sizeof(data)); // advance the pointer reference. ptr += sizeof(data); std::cout << std::hex << data << " " << std::endl; } int main(int, char**) { unsigned char buffer[] = { 0...

Are reference attributes destroyed when class is destroyed in C++?

Suppose I have a C++ class with an attribute that is a reference: class ClassB { ClassA &ref; public: ClassB(ClassA &_ref); } Of course, the constructor is defined this way: ClassB::ClassB(ClassA &_ref) : ref(_ref) { /* ... */ } My question is: When an instance of class 'ClassB' is destroyed, is the object referenced by 'Cl...

When do I need to deallocate memory?

I am using this code inside a class to make a webbrowser control visit a website: void myClass::visitWeb(const char *url) { WCHAR buffer[MAX_LEN]; ZeroMemory(buffer, sizeof(buffer)); MultiByteToWideChar(CP_ACP, MB_ERR_INVALID_CHARS, url, strlen(url), buffer, sizeof(buffer)-1); VARIANT vURL; vURL.vt = VT_BSTR; vU...

TerminateProcess and deadlocks

Is it real that the TerminateProcess function in Windows could hang because the threads inside the process were stuck in a deadlock? Example: Process A is running under Process B's control, now Process A gets into a deadlock and Process B detects this and decides to 'Kill' process A using TerminateProcess. Would it be successful in ki...

Fun with casting and inheritance

NOTE: This question is written in a C# like pseudo code, but I am really going to ask which languages have a solution. Please don't get hung up on syntax. Say I have two classes: class AngleLabel: CustomLabel { public bool Bold; // Just upping the visibility to public // code to allow the label to be on an angle } clas...

Why does DestroyWindow close my application?

I'v created a window after creating my main one but calling DestroyWindow on its handle closes the entire application, how can I simply get rid of it? it looks like this: BOOL InitInstance(HINSTANCE hInstance, int nCmdShow) { HWND hWnd; HWND fakehandle; hInst = hInstance; // Store instance handle in our global variable h...

Is it possible to load a file full of binary data into GDB when GDB is debugging a core file?

I am debugging a crash using GDB and a core file. A large portion of the memory space is mmapped into the process. That portion of the memory is not saved into the core file. I have a file that contains all the data in that mmapped memory. I would like to find a way to load the data from that file into GDB at a certain offset so th...

COM Pointers and process termination

Can an unreleased COM pointer to an external process (still alive) cause that process to hang on destruction? Even with TerminateProcess called on it? Process A has a COM interface pointer reference to Process B, now Process B issues a TerminateProcess on A, if some COM interface pointer to Process B in Process A is not released proper...

Policy based design and defaults.

Hard to come up with a good title for this question. What I really need is to be able to provide template parameters with different number of arguments in place of a single parameter. Doesn't make a lot of sense so I'll go over the reason: template < typename T, template <typename,typename> class Policy = default_policy > struct polic...

Why was the definition of a variable changed in the latest C++0x draft?

n3035 says: A variable is introduced by the declaration of an object. The variable's name denotes the object. n3090 says: A variable is introduced by the declaration of a reference other than a non-static data member or of an object. The variable's name denotes the reference or object. I wonder what motivated this change. Doe...

Using libcurl & SSL

Hi there. I've found there is really very little information around on this topic. I already have a dll making successful posts using libcurl. I've compiled libcurl with openssl for ssl functionality. Here is an exert of my original curl setup. curl_easy_setopt(handle, CURLOPT_ERRORBUFFER, errorBuffer); //curl_easy_setopt(c...

g++ linker error--typeinfo, but not vtable

I know the standard answer for a linker error about missing typeinfo usually also involves vtable and some virtual function that I forgot to actually define. I'm fairly certain that's not the situation this time. Here's the error: UI.o: In function boost::shared_ptr<Graphics::Widgets::WidgetSet>::shared_ptr<Graphics::Resource::GroupBy...